Monday, March 28, 2011

Space Warfare XIII: The Human Factor


Discussion of the recent post on Interstellar Empire led to a question that until now failed to get a post of its own: the role, in space warfare, of drones versus ships carrying human crews. Consider this deficiency now corrected.

A few provisos apply. Set aside for now the question of whether warfare, as we have known it and too much loved it since the Iliad, may be obsolescent as a viable mode of conflict among post-industrial communities.

Also set aside the Plausible Midfuture, a place where warfare in deep space is doubtful even if Earth orbital space is armed to the teeth. Set aside as well the general messiness of warfare on planets; my concern here is with space combat. We are dealing here with space armadas, a concept that is demi-operatic at least.

Will these armadas be made up primarily of warships with human crews - the familiar classical vision - or largely of robotic craft?

A lot of this comes down, I would argue, to good old money. The first 50 years of deep space exploration have been exclusively robotic because robotic spacecraft are cheaper. They are cheaper for several reasons: They can be much smaller; except for sample returns they don't need to come back; and in fact they don't even need to always get there.

So far as I can recall, every mission to the outer planets has (so far) been a success, but we only reached the point of batting .500 against Mars since I launched this blog. Such a loss rate was regarded as acceptable for human missions in the 16th century, but not in the 21st. (The more so because the enormous cost of human spaceflight, and resulting high profile, makes human spaceflight losses more controversial than, say, helicopter crashes.)

The situation in warfare is somewhat different, because soldiers are in some fundamental sense expendable - many of our military traditions are, in one way or another, built around that fact. But they are not lightly expended, if only because high quality crews are costly to train and difficult to replace. For post-industrial societies, where untimely death is no longer a sad commonplace, public resistance to casualties may be problematic even for authoritarian regimes.

Cost and risk of losses, taken together, are ample reason for the designers of combatant spacecraft to automate them so far as is practical. But how far is practical?


Kinetic weapons will have no human crews, for obvious reasons. There are almost equally strong reasons not to put crews aboard the buses that deliver them. Kinetics are most effective in a single wave that saturates defenses - the faster they are thrown the harder they will hit, and the less time the defense will have to stop them. This argues for a bus that uses its full delta v for maximum closing rate, rather than holding back propellant in order to recover the bus. For its basic mission it need not be very sophisticated, and you will not be re-using it anyway, at least not anytime soon.

So it is probably cheaper to make the bus expendable.

Lasers are a different matter, as are alternatives such as particle beams. (And for that matter kinetics, if these are slung on their way by coilguns. Flip side, bomb-pumped lasers are expendables, with military properties similar to kinetics.) A laser star is inherently reusable, and suited to missions, such as blockade or maintaining a 'presence,' in which repeated engagements may be required. A laser and its associated optics are also presumably sophisticated equipment. On all of these grounds putting a crew aboard a laser star seems much more plausible than putting one aboard a kinetic bus.

But what exactly would the crew be called upon to do? No gunners' mates are needed to shove photons into the breech, or even aim the laser. Actual precision aiming of the beam will be automated in any case, and assigning targets can be done from a few light seconds away.

The other traditional role of ships' crews is maintenance and repair. But drive engines and megawatt lasers do not, so far as I can see, provide much scope for onboard servicing, let alone damage control during battle. Repairs of either one pretty much need the services of a cageworks. Occasional replacement of smaller failed systems, or whacking balky parts with a wrench, can be done by service teams based elsewhere - at a space station, for defensive orbital forces, or aboard a tender for deep space constellations.

It is a peculiar fact that both many space emergencies - such as onboard fires or air leaks - and much of the corresponding scope for human emergency repair, relate specifically to life support habs. (Propellant tanks can also leak, but offer precious little chance of onboard repair.) I suspect, indeed, that life support maintenance will be a major role of space crews. But this sets up an odd circularity. Take away the hab and you eliminate many of the emergencies that a crew could respond to.


The final role for humans in space combat is command and control, especially rules of engagement decisions. We might not want to trust even high level AIs with these decisions - either because we are not quite sure of their motives, or because they have no motives at all, and so can free us of everything but the need to decide. But the scale and probable tempo of space combat are such that - as mentioned above concerning target designation - these functions generally don't need to be aboard the weapon platforms. Why not offload them to the 'tender' that provides teams for the occasional maintenance call?

Back in Part III of this series I gave the following description of a space combat constellation:

Taken as a whole you might call it a fleet. But it more nearly resembles a mobile, distributed, and networked fortification, deploying in action into a three-dimensional array of weapon emplacements, observation posts, and patrol details, all backed up by a command and logistics center.
But even supposing that a main battle force is built along these lines, what about smaller independent mission packages - the equivalent of a cruiser, for example, for patrol missions?

Contrary to the (understandable!) assertion of a well known Evil Website, space is not an ocean. At sea, a single 10,000 ton ship has major advantages over four 2500 ton ships. It is more seaworthy, far more comfortable for its crew, harder to sink, provides a higher and dryer command for guns and sensors, and can maintain higher speed with less power and fuel consumption.

In space these considerations apply with far less force, if they apply at all. A single large hab pod is likely preferable to several smaller ones - but only the command ship / tender needs a hab pod at all. And the other force elements can be carried as riders, if desired, separating only to deploy for combat.

If your propulsion tech involves an electric drive powered by an external reactor, which also supplies the primary laser, you want to match the drive, reactor, and laser, which does argue for putting them together aboard the same spacecraft. And you might reasonably be less than comfortable about separating the crew hab from the main drive. But if your setting has fusion drive, or any self-contained drive, this is much less a consideration.


One other human-factor consideration to keep in mind was brought up in the linked discussion by commenter Tony: What happens to the morality of warfare - such as it is - when no soldiers put themselves at risk to fight it, because the fighting is all done by robots?

In the scenario I have outlined above this is not really the case. The constellation has a human crew, aboard the command ship / tender, even if it is 'behind the lines' relative to the weapon platforms. If the combat units of its constellation are defeated the crew must retreat, surrender, or face destruction - the choices that have always faced combatants who were disarmed in battle rather than killed outright.

Discuss.



Related Links:

Atomic Rockets, of course - especially, but not exclusively, the pages on space warfare.

And previously in the Space Warfare series on this blog:

I: The Gravity Well
II: Stealth Reconsidered
III: 'Warships' in Space
IV: Mobility
V: Laser Weapons
VI: Kinetics, Part 1
VII: Kinetics, Part 2 - The Killer Bus
VIII: Orbital Combat
IX: Could Everything We Know Be Wrong?
X: Moving Targets
XI: La Zona Fronteriza
XII: Surface Warfare

Also ...

Battle of the Spherical War Cows: Purple v Green
Further Battles of the Spherical War Cows

Plus

Space Fighters, Not
Space Fighters, Reconsidered?

And, indulging in heresy -

Give Peace a Chance


The image shows Achilles fighting Hector.

875 comments:

1 – 200 of 875   Newer›   Newest»
Byron said...

Your analysis agrees with my own from a technical perspective. However, you forgot the real reason for manned warships: Burnside's Law.

Tim said...

Yes, without humans, we have no story. Now we need to come up with a justification for why we need humans on the battlefield. Perhaps there is some sort of galactic Geneva Convention that prohibits automations from making the decision to use force against humans. In other words, even if the weapon is remote, loads and aims itself, etc. a living human being must give the order to fire. The logic behind this is that mortal humans will be more accountable than machines, fearing much more the consequences of making an error in judgment. Like the Geneva Convention, not everyone is going to follow the rules, but if our protagonists do, we've at least got some room to write a story.

Byron said...

Yes, but there are several issues with that. First, that seems to allow the command ship to be used. Second, when does the human pull the trigger? Does launching a kinetic bus count? Or is there only a limited delay allowed? And then what happens when someone decides to cheat?
Another thing Rick didn't really mention is that in the past the consensus has been that patrol-type missions are less likely to be automated than the battlefleet.

onelowerlight said...

The problem with remotely controlled weapons posts is that they are more susceptible to jamming and hacking. If a major solar storm interferes with your signal, or the enemy is able to cut off your signal or hijack the platform with its own, then you've pretty much lost the platform. If you have a human crew there, they can still figure out ways to fight back and retake control.

In general, though, I think you're approaching this backwards. To figure out what a space war would look like, you've first got to establish what it is that they're fighting for. So what if you have the technology to build a remote weapons platform, when your only refuge is your remote moon base and that's what the enemy is going for? If humans are out there, war is eventually going to come to them, not the other way around.

I do agree, though, it's going to be very different, and will probably be much more automated than even our current wars.

Milo said...

You also have to ask what civilian space travel looks like in this future. If there are nearly no crewed vehicles anywhere, then it will be very difficult for the military to invent their own just for the purpose of warfare. (But then, without crewed space travel, how did you colonize the place that's doing the fighting?) If crewed space travel is (relatively) common and affordable, then it looks a lot more reasonable for the military to follow suit.



Rick:

"The first 50 years of deep space exploration have been exclusively robotic because robotic spacecraft are cheaper."

The first 50 years of deep space exploration have been exclusively robotic because current rocket engines take years to reach deep space (and twice as long if they need to carry delta-vee for getting back), and humans can't wait that long. Of course, there is also life support for such a long period to drive costs up, but that's moot point since people wouldn't put up with such a mission even if you put their head in a jar.


"So far as I can recall, every mission to the outer planets has (so far) been a success, but we only reached the point of batting .500 against Mars since I launched this blog. Such a loss rate was regarded as acceptable for human missions in the 16th century, but not in the 21st."

To be fair, having humans along would increase the success chance. (Humans are their own backup mechanism.) The question is by how much.



onelowerlight:

"The problem with remotely controlled weapons posts is that they are more susceptible to jamming and hacking."

It's going to be pretty hard to jam laser communications. The enemy's communication beams aren't going to be anywhere near you.

Dex said...

Does your setting have FTL Comm?

If not, you will want the afore mentioned constellation, which significantly reduces light-lag. Similar reasoning applies to missions for Earth-Moon L1 station in conjunction with lunar exploration.

This means there is a human component to your "spacecraft" and other than the C2 links is the most vulnerable component.

Fiber-Optic C2 is much harder to jam than a radio or even laser link. This all leads to the heavier craft to protect the C2/launch segments of your constellation.

The constellation begins to look more like a manned Capital ship with several teleoperated escorts.

Byron said...

And how do you do fiber optics in space? You can't exactly string wires between ships. And I really don't see jamming as a huge threat at the constellation level. Lasers can't really be jammed, unless something really weird is going on. Hacking isn't likely either. There won't be any open ports on the side of the ship facing the enemy.

Mangaka2170 said...

I've been contemplating this subject a lot recently (assuming my more recent comments on other threads didn't give it away...). More specifically, I've been trying to find the balance between automation and crew size, and I think I'm getting some ideas.

The two most prominent factions in my story, the Mars Defense Force and the remnants of the Earth Federation, are both quite different thematically. The ships available to the Earth Forces are holdovers and reconstructions from the Federation days (and therefore about 30 years out of date), and the Earth Forces themselves, despite academy training and greater military experience than anyone else, suffer from the limits of terrestrial spatial awareness (they tend to think of space combat like slightly different air combat) and a rigorously indoctrinated adherence to the chain of command (sometimes to the point where they won't do anything without orders) and a culturally reinforced perception of a manifest destiny (they still consider all extraterrestrial settlements their colonies, even though they've been totally independent for a generation).

By contrast, Martian military craft tend to be civilian ships converted into warships, but Mars' military/industrial complex cranks out some of the most advanced technology in the solar system; as a result, Martian ships tend to be heavily automated and often appear to be civilian transports until they're ready to strike. Martian military doctrine tends to be somewhat paranoid (like Cold War-era US intelligence paranoid), and tends to prefer intelligence and counter-intelligence operations (since it's easier to sneak in a person or information than a warship), but they tend to value independent action more than the Earth Forces (but they're more responsible for their actions when they do act on their own).

Tim's comment about a galactic Geneva Convention against the use of drones pretty much describes the military and cultural attitude towards them, as drone weapons were used essentially indiscriminately in the previous war of independence by the Earth Federation, and ended up causing a few atrocities.

Finally, all sides make use of space fighters. While their purpose is a more strategic one, specifically for force projection and support, the atmosphere-capable ones are sometimes used to get around the ban on planetary bombardment from orbit by launching a fighter towards the planet, have it strike its target from high altitude and return to orbit to be retrieved by the carrier (since the ban merely prohibits firing weapons at ground, sea or air targets from orbit).

I figure a warship's CIC would have a crew of about 7 or 8 (pilot, CO, XO (who micromanages ship-to-ship combat, among other things), sensor operator, comm officer, main weapon gunner (or support craft coordinator, for carriers), defense grid operator and on a group command ship, a group tactical coordinator (who advises the CO on the status and positions of nearby friendly ships)), and would be a spherical room that displays a real-time 360x360˚ panoramic view of the ship's surroundings from its perspective. This averts the tendency sci-fi works tend to have of displaying combat on a 2D map or inside a holographic globe that imposes an arbitrary range that always seems to be only a few dozen kilometers across.

This blog has been very helpful in helping me to get the science in my story to be mostly right (or at least plausible), but since it is fundamentally about people I do need to invoke Burnside's Law from time to time.

Byron said...

What do you mean "Cold War-era US intelligence paranoid"? Everyone is that paranoid, or more so, it's just that they don't show it.
I think a common problem with these discussions is terminology. We often use "drone" for any spacecraft that doesn't have people on board, ranging from my unmanned laserstars controlled from a ship a few light-seconds away, to an autonomous warship. I'll propose we use RD (remote drone) and AD (autonomous drone) for the two. The two are in many ways fundamentally different, and I personally don't like ADs, for many of the reasons given. However, that has more to do with AIs than with the advantages of a human crew.
The same issues don't apply to RDs, as the human decides what to shoot at.

Native Jovian said...

I think the two major forces that will push toward keeping your crew on the actual fighting portion of a warship in space is 1) the hard limit imposed on communications by the speed of light, and 2) the necessity of protecting your crew even if they’re not actually on the part of the ship with the guns (or missiles, or lasers, or what-have-you).

A warship is going to have defenses, both active and passive –- armor and point defense –- and all the attendant systems (a generator to power it, engines to move it, etc). You need this for both your crew (to keep them alive) and your weapons (to keep them active under fire). If you don’t have defenses on your hab, then you’re relying on the combat section to defend it. Against lightspeed weapons this is nearly impossible, and against others it’s risky. If one missile slips past your point defense, your crew is now toast –- and then the best you can hope for is a mutual kill while your combat section continues to fight on under automated control. If your combat section doesn’t have defenses, then your enemies laugh at you while they blow it out of space and then demand your surrender.

The thing is that these defenses are heavy. This goes back to the point about a single 10,000 ton ship versus four 2,500 ton ships. When all four are armed-and-capable fighting vessels in their own right, then that’s one thing – but when one of them isn’t contributing anything to the fight beyond the human bit of the command and control loop (whatever that actually ends up being –- maybe just pushing the "permission to kill people granted" button), that changes things considerably. Then what you really have is a 10,000 ton ship versus three 2,500 ton ships and one 2,500 ton target. (Well, let’s be generous –- without weapons or defenses, it might only be 1,000 tons. Still not good odds.)

If you put it all in the same hull, they you cut down on overhead (you only need one generator, one engine, etc), and you save on mass devoted to defenses by minimizing surface area (for a given volume X, one continuous object with volume X will have less surface area than X separate objects with volume 1/X each), which reduces mass spent on armor if not necessarily point defense. It also makes you harder to hit in the first place, which is always good.

There’s also the problem of having your human crew talk to your remote combat section in the first place. It’s a trade-off between speed of communication and risk. The closer you are, the smaller your comm lag, but the greater your risk. The farther away you are, the lower your risk but the larger your comm lag. If you’re a light-minute away, then your safely out of the battle, but your comm delay is two minutes. If you’re a light-second away, then your comm delay is only two seconds, but you’re pretty much in the thick of things as far as combat (at least with lightspeed weapons) is concerned, which rather negates the purpose of being on a separate ship in the first place.

It seems to me that the best solution is to simply put the crew hab in the combat section, which reduces the command lag to zero while simultaneously allowing for better protection of both crew and weapons. That setup doesn’t preclude you from launching remote drones that may be worth deploying and recovering (but then we get into the problem with space fighters), or possibly launching one crewed ship with several unmanned vessels slaved to its controls –- but either way, the crewed ship would be a fighter in and of itself, not a glorified escape pod putting along behind the combat hardware with a crew hab and little else.

Byron said...

Native Jovian:
You are familiar with the previous space warfare threads, right? Rick thinks, and I am reluctantly forced to agree, that laserstar duels will be "eyeball-frying contests." Also, a laser that can kill targets at a light-second is pretty good in my book (diffraction).
While your logic seems good in isolation, there are a couple things to consider.
First, crewing of vessels is a case where there are hidden costs to crewing ships. Rick has estimated that each man will take at least 5 tons of habitat. That adds up quickly, particularly when you consider placing a crew of 30 or more (the minimum I'd put on a long-endurance starship) on board. Second, you have to budget for things like shadow shields that wouldn't be needed on RDs. Third, that crew will need more protecting than a similar RD would. A properly-designed RD will keep working until it's pretty much a wreck. I can't say the same of a human-crewed vessel.
In certain scenarios it does make sense to place humans aboard, but not in the normal Plausible Midfuture War. For example, how many people does it take to fight a standard laserstar in a fleet battle?
1
(For those of you who missed those discussions, it's pretty much a single big laser, with a ship wrapped around it.)
However, to have that person aboard each ship, I'm going to need the aforementioned 30 people. If he's aboard a control ship, I need just him. The support personnel can be there and not duplicated across the entire fleet.

Cambias said...

I'm a bit puzzled by your reference to the command/tender being "behind the lines." There are no lines, especially if you're fighting against interplanetary-range kinetic weapons and laser stars with a range up to a light-second. Things are a bit more dispersed, but those humans in the command pod are going to be in the thick of battle if they want to be able to communicate with their weapon platforms. And if they're just giving "fire and forget" orders, why not do it from a comfy bunker back on Earth?

Byron said...

But I doubt that weapons will be powerful enough for light-second ranges. For example, a diffraction-limited laser with a 10-meter mirror and a 500 nm wavelength (blue-green) will have a spot diameter at 1 light-second of 9.15 meters (via laser weapon calculator). And under plausible midfuture assumptions, that's a pretty big laser. Kinetics aren't going to be fast enough to get across light-second distances on tactical timescales, either.
As to light-second delays being a major problem, you're suffering from air combat syndrome again. A second or two won't matter that much. Commands will be limited to "attack that target" and "cease fire". And it won't be over all that quickly, as both sides will likely open fire at extreme range. Plus, there's a delay in orders being executed today that's usually much greater than we'd see here, and nobody complains.

Native Jovian said...

Byron: I'm fine with that conclusion. My ultimate point was really that your crewed ship needs to be a fully-capable fighting vessel rather than just a tag-along afterthought. If your fleet is one crewed vessel with 30 crewman and 29 RDs, then so be it -- but I don't think that have a fleet of 30 RDs and one 30-crewman hab-with-engines is going to cut the mustard.

Byron said...

I'm not advocating leaving the command ship defenseless. However, it will be far too valuable to be used as a line warship. Think of an AWACS.

Milo said...

Byron:

"I'll propose we use RD (remote drone) and AD (autonomous drone) for the two."

Any drone is going to have some degree of both remote and autonomous behavior. Remote because even a fully sentient AI is still going to receive orders from its commanding officer, and autonomous because it needs to know what to do while waiting for communications lag, and even our HUMAN crewed ship concepts still feature glass cockpits.

A more useful distinction would be between drones that are remote-controlled from a nearby mothership, and drones that are remote-controlled from lightminutes away on their home planet.

Anonymous said...

One other thing to consider is to have the laserstar be the command ship and that it carry several RPV type fighter-drones (Byron's RD's); they can attack the other side's RDs and manned combat spacecraft; or defend against attacks from either of those. Laserstars would probably also carry 'fire-and-forget' kinetic busses and missiles to keep their enemies occupied while their main weapon is busy eye-ball frying. The bottom line is that you'll need to have Humans in the loop (and fairly close), not just for command and control, but for those unexpected situations that need Humans on the spot. Besides, war is a very human activity and I expect that we will come up with reasons to stay involved in it for the forseeable future.

Ferrell

Hugh said...

PW Singer in his "Wired for War" non-fiction book about military robots points out that the current day US military in theory wants humans in the decision loop, but this gets abandoned as soon as the time scale shortens below human reactions. He also discusses the strange psychological effects when remote drone operators are separated from combat by great distances.

Peter Watts in "Blindsight" (science fiction book) has humans leading robots in combat as a way of demonstrating commitment: our officers are willing to risk their lives. (Haven't got my copy on hand, so may be slightly misremembering this.)

Jack said...

You can't put people on anything that has to aim at very distant targets: movement disturbs the aim. Same reason that notions of manned space telescopes were unworkable. Has anyone calculated how massive a vessel would have to be before crew heartbeats had a negligible effect on aim?

ElAntonius said...

I remember a discussion I read a while back that amounted to this:

If the pilots of the (aircraft) drones attacking your military are safely in a base in San Fransisco, and after their shift is up they go home to their families for the night, how does one define "valid military target"? Drone pilots start fuzzying the lines drawn by the Geneva convention.

In the case of drone warfare in space, we're talking inherently about weapons of mass destruction. I agree with others here that if the parameters of space combat are such that you can safely command from outside of the battle, then you can do so from a bunker on the planet. Does that justify an orbital strike on a planet, potentially with massive civilian casualties?

We get upset when our opponents put military staff near hospitals, but as the remote drone rises in prominence I think we're going to start having to address those questions the hard way. Especially because drones can be built quickly and cheaply...I can see a future where the only way to win is to knock out the CIC of the opponent.

I maintain that the only real way to get the tropes we all know and love (relatively close range fighting between agile, small-crew craft supported by comparatively massive expensive craft) is complex warfare in orbit.

If you can't be indiscriminate, it becomes easier to justify humans on board. If missions are measured in hours to days, it becomes easier to have "fighters" (gunships really, I think that term sounds cooler).

The only thing it doesn't work for is opera, but a few limited dogfights in orbit around Mars makes for exciting space combat even if it's not a war to the knife.



The standard sci-fi future history addresses Burnside with a simple handwave: "The AI War of 2142 lead to an Alliance-wide banning of AI and computer controlled warcraft."

It's a cliche, but it's common because it pretty much works.

Bryan said...

I think the biggest possible reason to keep humans is one of the less romantic - redundancy.

In an AI-controlled ship, take out the AI you take out the ship. With humans, the loss of one can be dealt with by having another crew member replace the dead/injured one. You could conceivably loose a lot of the "top brass" on a ship and still maintain a functioning ship, as lower-ranked officers are usually trained to fill the gap left by a superior.

Likewise, the ability of humans to function while injured, and recover, may also have some value. Unless AIs are based on some radically different tech than todays computers, even minor damage could lead to catastrophic failure.

Of course, all of the above assumes that cost, energy consumption, size, or some other factor is limiting for AIs. If they fit on a penny, cost as much as a cup of coffee, and can run a year on a 'AA' battery than all these issues go away.

Bryan said...

One other human-factor consideration to keep in mind was brought up in the linked discussion by commenter Tony: What happens to the morality of warfare - such as it is - when no soldiers put themselves at risk to fight it, because the fighting is all done by robots?

I don't think this changes much. At the end of the day warfare will still have the same purpose as today - to achieve some political goal, to control resources, gain territory, etc. While "morality" may not have much meaning when robotic ships blast robotic ships, the victor will still end up with a moral issue, as eventually their robots will encounter humans - for example the people occupying an asteroid/station/planet the victors covets. How you deal with those people will always remain an issue.

Given human history, I don't have much faith in these sorts of things ending "morally"...

Byron said...

Milo:
True, but only to a degree. There's a world of difference between a drone I tell to "patrol that sector" and a drone I tell to "attack that target, while maintaining this course and acceleration".
Another way might be to think of them as "Captain Drones" and "Admiral Drones". A Captain Drone, my RD, fights itself, but all the orders a captain would give (course, acceleration, targets) come from a human. An Admiral Drone only receives the orders an Admiral would give. (Go here, engage the enemy)

Hugh:
That mostly applies to air combat situations, where human reaction times are really important. The same is not true of space warfare. Either the scale is way above or way below human times.

Jack:
I don't think that a weapons-grade laser will be that worried. If it's a chemical laser, then the machinery will be far more disruptive than the humans will.

ElAntonius:
No. Air warfare is unique because the crews have costs on the same order of magnitude as the vehicle. The same isn't true in any other realm, and it won't be true in space. The drone will almost certainly be far more expensive than the people, so there's no strategic reason to go after them. (That isn't to say people won't shoot at the command ship. They will. However, that's on a tactical level.)

Bryan:
Humans are going to be far more fragile than a computer-controlled system. My RD battleships have a dozen computers, dispersed throughout their structure. Any three of them are capable of fighting the ship. This means that the enemy has to destroy over three-quarters of my ship to take out enough computers. I can almost guarantee you that humans wouldn't still be fighting. We're comparatively squishy, and half the remaining crew would be off fixing the life support.

Milo said...

ElAntonius:

"The standard sci-fi future history addresses Burnside with a simple handwave: "The AI War of 2142 lead to an Alliance-wide banning of AI and computer controlled warcraft.""

Which is the rough equivalent of banning pencils because you poked out your eye.



Bryan:

"In an AI-controlled ship, take out the AI you take out the ship. With humans, the loss of one can be dealt with by having another crew member replace the dead/injured one."

You can have several redundant computers on a ship. In fact, we already do.


"You could conceivably loose a lot of the "top brass" on a ship and still maintain a functioning ship, as lower-ranked officers are usually trained to fill the gap left by a superior."

Redundant computers would have identical programming, and so would all be equally competent and fully capable of taking each other's jobs.


"Likewise, the ability of humans to function while injured, and recover, may also have some value."

Injured? It's already impressive that humans are able to get back up and return to their station after being knocked across a room.

AIs might be designed to be sturdier and harder to damage than humans, but they will have little capacity for repairing any damage that is still sustained, except by rerouting to a redundant backup that hasn't been damaged yet. Humans, meanwhile, are their own redundant backup.

Byron said...

Milo:
Humans have no more capacity to repair damage to ourselves on a tactical timescale than computers do. Particularly in space warfare, the energies involved are so high that I don't think you'll have very many wounded. People will be either fine or dead.

johnnylump said...

If we simplify away the need for humans to maintain a spacecraft in a timely fashion, and we assume no instantaneous communication regardless of distance, it strikes me the key variable is how far away away a state is comfortable being from its weapons -- for ethical, tactical or strategic reasons; it doesn't matter.

If you insist the distance is a matter of meters, then you need a human crew. This might be the case if AI isn't very sophisticated or trustworthy -- you want a captain on the spot making the call whether to pull the trigger or not.

If it's light-seconds, perhaps a mothership-drone combination is ideal.

If it's light-days, then you are probably comfortable with pure robotic warfare.

Other variables in play:
-Software/AI quality
-Weapon complexity (ie a large ship with dozens of weapons with different uses versus a missle)
-Resources available? I wonder if a drone-heavy military might burn through resources faster because there is less incentive to bring home robots versus manned craft.

Tony said...

Let's see...

1. The limitation on robotic spacecraft is not likely to be ROE considerations, morality, or even communications time lag. The limitation is going to be the expense and rarity of weapons and military grade sensors and propulsion systems. Resources are not unlimited, and there is a hard limit premium equipment, which means a hard limit on platforms. this leads to...

2. Laserstars are a waste of resources. If you're going to have a fully capable spaceship, mounting a single weapon system on it, no matter how powerful, is not going to be effective. Throughout history, military weapons platforms have always been multiply armed, Ships of the line had small arms so that an enemy couldn't clear your decks with small arms fire in close action, and so that they wouldn't be defenseless in resisting boarding attempts. In the age of steam, capital ships not only had their main armaments, they also had anti-torpedo boat guns, anti-aircraft guns, and some even had torpedoes. Aerial bombers still needed defensive machine guns. When the US tried to field an air force with exclusively missile-armed fighters, it turned out that they still needed guns. Even individual riflemen can have grenade launchers, rocket launchers, and bayonets.

A laserstar would need defensive systems. And then it might be equipped with missiles or even kinetic bombs for strike missions against planets/moons/asteroids. (Because if there are no enemy ships to shoot mondo photon hoses at, the laserstar's value is in its sensors and propulsion.) Pretty soon it becomes so complex that we might as well put a permanent maintenance and combat crew on it.

3. The assertion that remote drones would be more durable in combat than unmanned systems just doesn't stand up. In ship-to-ship fighting, on the sea, in the air, or in space, the idea is to kill the opposing machine. The fate of the crew, whether wetware or hardware, is secondary. If you can disable a drive or weapon system, or destroy the whole ship outright, whether it has people onboard or not, is irrelevant.

Tony said...

WRT the received wisdom from Atomic Rockets that fighters aren't justified in space warfare...

Well, we still send small probes out to the planets, rather than just observe with the Hubble Space Telescope. Why? Because it turns out that relatively limited sensors, if they are sufficiently closer to the subject of investigation, have more resolution than the best sensors millions or billions of miles away. Also, putting a person in the loop on the close-up sensor platform improves response time to emerging events.

Of course the cost/benefit decision on fighters would be very context dependent. They would only be justified by the right combination of time, distance, and cost factors. But I don't think we can rule them out entirely.

Geoffrey S H said...

So as to avoid making an ignorant comment and being (rightly) vented at, I will make one pathetic case for humans (well, not even that) and then not make any more posts.

I have a future history that essentially has humans completely leave the military as a useful force, but then some magitech hand wavium leads to them being forced back in some centuries later4- essentially a device allows them to compute alittle faster than robots, with expendable robots used sometimes, amnd more valuable humans replacing them dependig on the mission. This requires a laughably silly ability on the part of humans to control weapons and sensors with their mind, with greater precision than the robots. This is impossible.

Thinking about it, given how it took Byron to make me see how I'd insultingly refused to accept realty as per planetary invasion and learn my lesson, I will not push this point any further and hereby abandon the idea. I apologise for any ignoring of comments here. I will not comment on this again.

Happy debating!

Milo said...

Tony:

"In ship-to-ship fighting, on the sea, in the air, or in space, the idea is to kill the opposing machine. The fate of the crew, whether wetware or hardware, is secondary."

This wasn't always the case. On sailing ships, boarding actions aimed to remove the enemy's crew and replace them with your own, without directly targetting the ship. They also had grapeshot, which was highly ineffective at damaging anything except crew members, but was still useful because disabling a ship's crew members would stop it from fighting.

Penetrating radiation beams could be a space-age equivalent of grapeshot, killing crew with radiation poisoning without carrying enough energy to deal structural damage.


"Well, we still send small probes out to the planets, rather than just observe with the Hubble Space Telescope. Why? Because it turns out that relatively limited sensors, if they are sufficiently closer to the subject of investigation, have more resolution than the best sensors millions or billions of miles away."

This is more light cruiser warfare than fighter warfare, though. It doesn't justify carrier operations, because a space fighter isn't going to get that far from its mothership before it runs out of fuel or life support. You need a vehicle capable of extended solo missions in remote reaches, with all that implies.

Geoffrey S H said...

p.s: Forgot to state that my little Future hisotry had humans and robots replacing each other every few centuries due to the ebb and flow of new technologies that would facilitate this transfer.

Tony said...

Milo:

"Penetrating radiation beams could be a space-age equivalent of grapeshot, killing crew with radiation poisoning without carrying enough energy to deal structural damage."

THere are some serious practicality issues with that. You either have to have a wide beam to ensure enough cooking (wasting a lot of power on empty space), find a way to get right on top of the target to be able to maintain targeting against jinking, or have a nuclear bomb level energy flux in your generator in order to get enough energy on target in the short burst time that you have at longer ranges. I think weapons designers and tacticians would prefer to attack the enemy vessel. It's simply more practical.

"This is more light cruiser warfare than fighter warfare, though. It doesn't justify carrier operations, because a space fighter isn't going to get that far from its mothership before it runs out of fuel or life support. You need a vehicle capable of extended solo missions in remote reaches, with all that implies."

Depending of course on your technoligcal assumptions, I would think that you would probably wind up with something intermediate between a full capability ship and a single-seat fighter. Perhaps a gunboat with a pilot/commander, sensor manager, and weapons manager. Maximum endurance would be a couple of weeks, and the primary mission would be scouting and enemy defense saturation strike missions.

Byron said...

Tony:
OK, so a laserstar might have a few extra PD weapons. That still doesn't change the fact that it's pretty much one big laser, and that it will likely only require one person to run. Trying to do everything in a ship is generally really expensive, and not terribly effective. I'll try to get to your point about crewing later.

The assertion that remote drones would be more durable in combat than unmanned systems just doesn't stand up.
Is that supposed to be manned systems? I would argue that it does. It's like having a centralized brain versus one spread throughout the body.

Space probes are used because photos aren't everything, and plus, Hubble can't get the same level of detail. I still see it as a use of drones, though. You can avoid the mass penalty of humans, on a tactical level, the humans are close enough for recon use, and strategically, you don't need instant response.

One thing I would like everyone to keep in mind: Before you complain about lightspeed lag, remember decision lag in combat today. On a warship, I expect that orders take a while to get passed down. Far longer than the lightspeed lag on my proposed drones. And they do just fine.

Milo:
And boarding actions stopped when weapons became lethal enough to render them suicidal. The reasons were threefold:
1. If you captured the enemy ship, you got to keep it. They were expensive, and there was prize money.
2. It changed the battlefield significantly. You could win even if your ship wasn't as good.
3. It was really hard to destroy an enemy ship without boarding.
The point is that they don't happen any more, and they won't in the future.

Mukk said...

I am in favor of 29 drone laserstars/kenetic buses and 1 manned laserstar.

The manned laserstar will hang back, but it will be just as functional as a drone laserstar in combat, if only for purposes of point defense.

There may even be some ratio that certain militaries come to use. For every 5 drone laserstars the United states deploys a mannned one to comand them. That way they have some C&C redundancy in larger battles.

This seems the most logical way to operate. You want your humans just as well defended as your drones. And I'm pretty sure we have established that one big laser is preferable for point defense as well as attack. It means that you have a human componenet for stories that can die or be injured in the combat. And you don't have to do any handwaving 'drone ships are bad.'

Raymond said...

Tagalong.

ElAntonius said...

Byron: While I agree that drones in air combat are not the same as in space combat, I think there's still a truth to it.

Sure, laserstars are a huge investment, but what about kinetic buses?

What if you KNOW that you can target the CIC ship and knock out 30 drones? What if the CIC center is in a major metropolitan area?

Regardless of the cost of the actual drones, separating the man from the weapon he wields raises uncomfortable questions about the nature of warfare and what is acceptable in the pursuit of victory.

I'd love to see a story address it, actually.



While I agree that the "AI War" excuse usually feels somewhat flimsy, people are odd. Without getting too political, it's not like current governments don't ban all sorts of vaguely silly things on absurd notions of public danger...presumably a bad enough atrocity or set of atrocities could impede all sorts of progress in various fields.

For an easy precedent, look at the American reluctance to build nuclear power plants, or Prohibition.


If anything, I think justifying people in space is easier than justifying all sorts of other, bigger issues...like "what are we fighting over up there anyway?" Answer that and the human factor becomes easier...where there's people, there's the potential for violence, and where that exists, you can write about the crew of an armed space ship.

Justifying manned warships is really just justifying manned space travel and war in space at the same time. Find why we're up there, and why we'd fight for anything up there, and you find the reason there will be human stories on Battlestars.

Tony said...

Byron:

"OK, so a laserstar might have a few extra PD weapons. That still doesn't change the fact that it's pretty much one big laser, and that it will likely only require one person to run. Trying to do everything in a ship is generally really expensive, and not terribly effective."

"[T]rying to do everything" is a straw man. No designer ever does that. But having an ability to do a little bit of most things, plus a primary capability designed for the ship's doctrinal mission, is just plain sense. Remember, even supersonic fighters need guns.

And I'm not sure I buy into the utility of one big laser. Since we seem to be taking as many cues as possible from Atomic Rockets, it might serve everyone well to review the space war weapons page that deals with lasers. It turns out they probably aren't very long ranged weapons. That means the dominant weapon system is still going to be the guided missile.

"Is that supposed to be manned systems?"

Yes.

"I would argue that it does. It's like having a centralized brain versus one spread throughout the body."

You disable a weapon, sensor, or propulsion system, it really doesn't matter if you kill people along with it. Things that kill people tend to damage ships as well. If you want to make the argument that there will be only one manned bridge, but there could be numerous battle computers, you're wrong on two counts:

1. There can always be an auxiliary control, or even two, and

2. Damage that can take out primary control probably disrupts internal communications as well, possibly to the point that no alternate control site can fight the ship.

"Space probes are used because photos aren't everything, and plus, Hubble can't get the same level of detail."

I believe that's what I said.

"I still see it as a use of drones, though. You can avoid the mass penalty of humans,"

Depending on other factors, that could be a false economy.

"on a tactical level, the humans are close enough for recon use,"

Maybe humans are close enough. Maybe they aren't.

"and strategically, you don't need instant response."

You mean operationally. And that's not certain. See the Battle of Midway for the advantages of immediate response to emerging information.

"One thing I would like everyone to keep in mind: Before you complain about lightspeed lag, remember decision lag in combat today. On a warship, I expect that orders take a while to get passed down. Far longer than the lightspeed lag on my proposed drones. And they do just fine."

This is yet another straw man. There will always be decision lag. That doesn't mean that adding to it is advisable. In tactical situations between maneuvering and shooting spacecraft, it may be that seconds count.

Anonymous said...

Moving a little bit away from the big battle scenario, not all situations will need a huge warship equipted with Big Ass Lasers (BAL's); ordinarily you'd only need a smaller ship either heavily weighted toward one mission, or with a more general purpose design for flexibility. The point is that smaller ships require less resources to construct, man, and operate than a huge Laserstar; plus, more ships means more places you can be at. Also, modern weapons are such that it only takes one to wreck or destroy anything smaller than a Star Wars-type Deathstar, no matter the size (down to a certain limit, of course) of the launching platform. So, yes, if you accept that there should be humans onboard command ships for battle constellations, then they certainly need to be on board smaller warships,whose missions means more isolated locations far from headquarters and dealing with human-driven problems.

Ferrell

Bryan said...

Byron/Milo:

Both of you replied to my post, while ignoring the caveat I placed on my own reply:
Of course, all of the above assumes that cost, energy consumption, size, or some other factor is limiting for AI. If they fit on a penny, cost as much as a cup of coffee, and can run a year on a 'AA' battery than all these issues go away.

At the same time you both ignored your assumptions that AI is not limited by cost or support issues. AI redundancy may not be possible due to cost or support requirements.

I'd also point out that your assumptions about durability of humans verses computers does not fit the reality of today. Compared to todays computers, humans are much more durable - we're insensitive to "doses" of EMP that will destroy even hardened electronics. Likewise, we can continue to function relatively normally for hours-to-days after receiving doses of ionising radiation that would render electronics inoperative. Meaning that a human operated ship in a nuclear war could have advantages over a completely computerised one - at least in the context of "hits" that don't simply vaporise the ship (and assuming the ship/weapons can be operated without computerised assistance, etc).

Likewise, even injured, we're capable of preforming tasks, if at a diminished capacity. Computers (at least today) are all-or-nothing; one damaged trace on a microchip destroys that circuit.

You're also ignoring the economic side of war - war is expensive, AI may be expensive. People have been, currently are, and probably always will be, cheap.

Byron said...

ElAntonius:
There would likely be multiple CIC ships, and each would be heavily defended. And men have been separated from weapons ever since people started throwing rocks.
As to the city, I don't see that as likely unless you're fighting in orbit. See my comments about tactical vs. strategic/operational.

Tony:
One big laser is better at range than a bunch of lasers of the same total mass. Do the math yourself.
As to redundancy, if you properly distribute the systems, the ship will have to be pulped to be shut down. Your arguments apply mostly to manned ships. Yes, there could be an auxiliary control, but you've just added more mass and cost.

Maybe humans are close enough. Maybe they aren't.
Again, I don't see how this makes sense. There's no stealth in space, and if you do need to get sensors closer, you're putting the platform at risk. A drone will be much harder to detect than any medium-endurance manned platform (computers for a given task are smaller than humans) and it can be chilled.
As to lightspeed lag, what is the lag from modern recon stuff? A couple seconds? Maybe a few minutes? How much is lightspeed lag? Plus, nothing can be done before the information gets back to base, anyway, and human presence doesn't change that. So no, I don't see the point of manned tactical recon. (And I would classify Midway as tactical.)

Disclaimer: I am using plausible midfuture assumptions. These include things like interplanetary spacecraft with accelerations in milligees. So a few minutes of lightspeed lag is not going to make a huge difference, and it's far cheaper.

Byron said...

Bryan: When did I say anything about AI? We're speaking of computer control here. That is to say, I tell the computer what to do, and it does. We do it today.
As to the advantages of humans, we will be working through the computers anyways, so if the computers get hit, the ship is dead either way. All I'm doing is moving the humans somewhere else.

jollyreaper said...


We get upset when our opponents put military staff near hospitals, but as the remote drone rises in prominence I think we're going to start having to address those questions the hard way.


We always get upset when the enemy refuses to stand up and get properly killed like we want them to. If we're willing to pull our punches because of civilians getting in the way, our out-manned and out-gunned enemy will thank heaven for small favors and use them to their advantage.

jollyreaper said...

Especially because drones can be built quickly and cheaply...I can see a future where the only way to win is to knock out the CIC of the opponent.

I think this is the bigger factor. Germany and Japan lost WWII because they ran out of men and the means of effectively training them. If I recall the production figures properly, Germany was turning out more planes per month in the final months of the war than it was in the beginning. Lack of pilot candidates and lack of proper fuel for training them meant those planes were flown by amateurs when they were even flown at all. Now imagine that you're installing combat AI and a war machine fresh off the lines is just as capable as one that's survived the whole war. Of course, the other side is likely fielding similar war machines so the fighting remains that much more intense.

If you consider how capable the V1 was as an airframe, the only thing it lacked for was a suitable guidance system. That was years off, of course. Just imagine how difficult D-Day would have been if the Nazis could have accurately spammed the invasion fleet with a thousand buzz bombs. Imagine how different the final campaign in the Pacific would have been if the suicide rocket planes were true cruise missiles, especially ones that could be fired from sheltered positions on land. You might say that starts looking like charging machine gun nests across no-man's-land all over again.

Raymond said...

A few things:

- Tony, I don't quite buy the "hard limit" on propulsion units, powerplants, sensors, etc. I don't see any technical or industrial reason why smaller and cheaper powerplants couldn't be produced in greater numbers, especially by an economy on a war footing.

- On performance, it should be noted that mass penalties affect not only propellant requirements, but burn time (for a given power level). This affects the strategic mobility of the constellation as a whole, not just tactical movement. The mass penalty of a hab impacts strategic movement much more than tactical, at least for Plausible Midfuture propulsion tech.

- Kinetic buses have very different propulsion requirements than laserstars would - the former benefits from quick acceleration and high closing speed, the latter benefits from long range and low closing speed. Not to say both wouldn't have elements of the other's weapon systems, but the nature of the primary weapon is a major factor in propulsion unit design.

- Related to the above, eyeball-frying range is going to be a lot longer than even point defense range with a large laser; I imagine typical tactical maneuvering will center around forcing the enemy's lasers unshuttered for a mirror-kill, then following up with kinetics.

- Even if laserstars (as a general class of craft whose primary weapon is a big laser, whether or not it carries additional kinetic weaponry) are crewed, kinetic buses are less likely to be so - if only because they are so much less likely to survive, or be retrieved promptly.

- The class of craft used for smaller missions than large-scale straight-up constellation-level fights are also, IMHO, the most likely candidate for command craft. The kind of sensor and comm packages (and crew to interpret them) suited to long-range patrol missions and show-the-flag operations would likely have a fair amount of overlap with the ones used in constellation warfare.

Tony said...

Byron:

"One big laser is better at range than a bunch of lasers of the same total mass. Do the math yourself."

Only if it can be held on target long enough -- or even hit it at all. That's highly questionable.

"As to redundancy, if you properly distribute the systems, the ship will have to be pulped to be shut down. Your arguments apply mostly to manned ships. Yes, there could be an auxiliary control, but you've just added more mass and cost."

The same argument could be made for a "properly" distributed crew. And if the ship is big enough that it can still be fought after a hit, the mass of crew accomodations is marginal. And any crewmembers surviving a hit can do things like repair or reroute broken data paths, clear debris, etc.

"Again, I don't see how this makes sense. There's no stealth in space, and if you do need to get sensors closer, you're putting the platform at risk. A drone will be much harder to detect than any medium-endurance manned platform (computers for a given task are smaller than humans) and it can be chilled."

No stealth in space is a statement of theoretical principle, not practical application. It implies that if you could look everywhere at once with powerful enough instruments, you wouldn't miss a thing. But you can't look everywhere else, and your instruments will not be as powerful as possible. So you will have to distribute your instrumentation and focus on bodies of interest. Putting decisionmaking capabilities close to many -- or even all -- of the instruments throughout the distribution only makes sense.

"As to lightspeed lag, what is the lag from modern recon stuff? A couple seconds? Maybe a few minutes? How much is lightspeed lag? Plus, nothing can be done before the information gets back to base, anyway, and human presence doesn't change that. So no, I don't see the point of manned tactical recon."

The point is being able to make tactical decisions immediately, rather than a few minutes or seconds in the future.

"(And I would classify Midway as tactical.)"

The Battle of Midway was a military operation. The tactical level of combat in that operation was the level at which aircraft interacted with each other and with target surface vessels.

"Disclaimer: I am using plausible midfuture assumptions. These include things like interplanetary spacecraft with accelerations in milligees. So a few minutes of lightspeed lag is not going to make a huge difference, and it's far cheaper."

In that context, any force that sends manned spacecraft to fight in a battlespace, rather than try remote control from a planetary body, would win easily. Even in the context of tactical combat around a planet or asteroid, it should be obvious that there is no direct line of sight between all possible orbits that one might wish to occupy. Having multiple manned platforms capable of fighting themselves might just be a good idea if the enemy attacks your comm satellites, or takes out your command craft at the beginning of an engagement.

Byron said...

So far, I've mostly attacked points in favor of humans. Now it's time to raise my own:
1. Cost/Performance. No spacecraft will be using humans to aim or load weapons, man the helm, etc. The humans will basically all be in modern officer roles. For an example of this, look at the Russian Alfa class submarine.
However, this means that if we have two ships, one an RD and one manned, that are otherwise identical, the manned one will be far more expensive. I'll use an example from my Rocketverse setting, which was based on the best consensus numbers I could find.
For a medium laserstar, I built a ship. The drone version was 466,654.65 kg loaded, while the crewed version (18 men, 180 days [which I think is smaller than practical]) was 608,965.35 kg loaded. Delta-V is the same, and external armor was scaled to the new design, but the engine and other systems are the same on both. I'll send anyone who wants it a copy of the spreadsheet.
Is a 30% increase in mass, with corresponding drop in performance, really a good idea? I could build a lot more drones for the same cost. I will admit that as ships get bigger, it makes more sense to add people. If the drone was, say, 5 megatons instead, the added mass penalty would be hard to notice. However, that's outside plausible midfuture.
2. Lack of risk to human life. This has mostly been raised by the other side, but it's really on mine. Humans are always trying to find better ways to kill, and if I can launch an attack with my drones while my men are safely in the back, I will. People don't care as much about morality during a war. They want their people home safe, and don't care that much about other stuff. I know there are exceptions, but take a look at World War II.

Byron said...

In that context, any force that sends manned spacecraft to fight in a battlespace, rather than try remote control from a planetary body, would win easily.
That's a deliberate strawman. I'm advocating controlling ships from a few light-seconds, or less. Pretty much just outside effective range of the enemy. The difference in decision lag isn't enough to make up for the greater numbers I can field. And if it's too great, I just add more armor to the control ship, and bring it closer.

Only if it can be held on target long enough -- or even hit it at all. That's highly questionable.
You are aware of the fact that a laser will also work as a telescope. Point it at the target and pull the trigger.

You seem unfamiliar with the purpose of recon. It's to get information to the commander. The commander then acts. Manning your recon platforms doesn't really help, as the lag loop is still just as long. Unless you put the commander in the recon platform, and send him out in front. What a great idea!

Z said...

I feel like some of the most pertinent considerations to whether you have warships or drones have yet to be raised, because they are too messy to fit into the space-battlefield-as-spreadsheet we have all come to know and love :-)

To be sure, there will be remotely operated or gently autonomous combatants. Space combat puts a premium on infinite patience, split-second vector math skills, taking orders, dying without a fuss and not taking much in the way of baggage weight, and that's a list that strongly favors plucky robots. Nevertheless, I think there might still be some room for well populated pew-pew battlecruisers- as war on paper almost uniformly neglects the things people actually do. There's a reason that a merchant ship of a given weight might have a crew of tens and a warship of the same displacement might have a crew of thousands, even though the warship crew has a much greater incentive to be elsewhere, and it's not because they are turning the capstans.

First, shit is finicky, and military shit tends to be more so. I don't know about other people's experiences around big power plants, but in mine, whether it's on a boat, a plane, or a power grid, there's no way of packing several megawatts of power into a box that does not require the massage of wrenches in intervals usually measured in hours. A megawatt laserstar reactor might not be a clanking Victorian beast, but it will have turbines, and pumps, and valves, and it will need tending. There has been mention that a big laser will take one person- to pull the trigger- but I call shenanagins. I've seen the lasers that presenting exist that might make tolerable spaceship weapons, and they are big engines with a certain proclivity for inventing ways to set themselves on fire. Even big static piles of missiles need to be maintained. The fact that military systems are invariably higher performance system also means they are less inherently reliable. The point was made that we don't want to be sending people out when spaceships just work half the time- I think that neglects the flipside that half-billion dollar spacecraft have been lost for want of a thump on the side of the box. Rick didn't seem keen on major repair work, but let's not forget the ISS was put together with a crane that can barely support itself on Earth- in zero g I could imagine pulling out the reactor with little more than a carjack, and setting it aside on a bit of clothesline.

Secondly, you need to multiply that need by the number of science-fictionally-wicked systems onboard- and military ships have lots, and lots, of system. Every craft is invariably a multirole craft. The growth of additional systems on a ship or aircraft over the course of its life can be reliably measured in pounds per day. A lot of these will be competing for limited active resources, and so you'll want to move them, or unplug them, and I imagine that somewhere the line between adding redundancies and self-repair capabilities it just looks easier to have a Countermeasures Officers, or Oscillation Overthruster's Mate, or whatever.

(cont.)

Z said...

(cont.) Lastly, despite the finicky nature of overspec engines, and equally finicky battledamage, a warship has a considerably higher premium on continuing to function. Merchants vessels get to wait, a plane has to be in the air for six hours and would die before it could be fixed (plus that making repairs in a Mach 2 windstream bit,) but in space, repairs are both possible in the absence of a terribly hostile surround, and given the long lead times for replacements to arrive, there is a premium for staying on station.

The best way to accomadate all those disparate requirements might be to have a very versatile multi-role device onboard- like a person. They can also make decisions pertinent to a situations in tens of seconds instead of tens of minutes, they can't be jammed (and yes, laser comms can be jammed too- if you bother to do them at all,) can render aid to passenger ships, and so on.

All of this, of course, can be used as an argument for something between a tender and a carrier. But
when the tender needs an peppy engine to keep up, and is still in the field of enemy fire along with its charges, and so on, exactly when does it make more sense to just make a battlestar?

Tony said...

jollyreaper:

"I think this is the bigger factor. Germany and Japan lost WWII because they ran out of men and the means of effectively training them..."

No they didn't. They were faced with larger, more efficient (for certain values of "efficient") economies that bludgeoned them to death. The fact that German (and to some extent Japanese) war economies got larger over time is irrelevant. They didn't get as large as they could have gotten without bombing and submarines. That they were both low on fuel at the end just shows how bad things had gotten in the resource war.

"If you consider how capable the V1 was as an airframe, the only thing it lacked for was a suitable guidance system..."

The V1 as a cruise missile would have been easy enough to defend against, provided the Allies suspected even a little bit that it had guidance. Fighter aircraft could down them easy enough, and attacking a vessel brings a missile within that vessel's defensive envelope. It would have been bloody, but probably no worse than kamikazes off of Okinawa.

Besides, given the likelihood that a strike aircraft of any nation would come back from a anit-surface ship attack mission during most of the war, they were all effectively cruise missiles anyway.

Raymond:

"Tony, I don't quite buy the "hard limit" on propulsion units, powerplants, sensors, etc. I don't see any technical or industrial reason why smaller and cheaper powerplants couldn't be produced in greater numbers, especially by an economy on a war footing."

Yeah, they put smaller and cheaper propulsion plants and sensor suites on escort carriers in WWII. They had to be carefully managed to keep them away from real enemy fleet units. Look up the Battle off Samar, 25 October 1944.

Raymond said...

Tony:

"And I'm not sure I buy into the utility of one big laser....That means the dominant weapon system is still going to be the guided missile."

And with no stealth in space (and long detection ranges) the only defense against an incoming missile is to shoot it down. Lasers are best for this. Bigger lasers are better, and the scale isn't linear. The exact balance between lasers and missiles depends entirely on your assumptions about laser efficiency, mirror cost, and power per unit mass; whatever the specific balance, though, twice as big a laser is more than twice as useful.

Bryan:

Given how much of the operations of the craft will be entirely dependent on computers (especially for fire control), the fragility of computers is the limiting factor whether or not the craft is manned.

jollyreaper said...

Regarding armaments, there's been a tendency to unify. The early battleships with turrets carried mixed caliber guns and later were unified to "all big guns" for primary offense with secondary batteries strictly for close defense.

Early tanks had turrets all over the place but we later standardized to one big gun with differing combinations of machine guns -- coaxial with the main gun, commander pintle mount, etc.

That's a good point with dropping the gun too soon in Vietnam from manned fighters but, as I've noted before, the last gun kill against an aircraft was by an A-10 against an Iraqi helicopter. That goes for the USAF and Navy. Have there been any gun kills elsewhere in the world? I don't think anyone would want to fly without a gun -- I know I wouldn't -- but I wouldn't expect I'd be needing to use it but for dire emergencies. The but the missiles are so much more capable these days and the enemy always outnumbered. It might be a different case if we were routinely seeing dogfights where missiles are expended and pilots are forced to resort to guns. Frankly, it's rare that an American pilot even has a chance of encountering an enemy aircraft, let alone ever needing to fire a missile at it.

As for the defensive armament on heavy bombers, the tail gun was the last thing to go on the jet bombers and as far as tactical attack aircraft go it was seen to be more useful to combine speed and armor and nix tailguns. The Skyraider has been called the ultimate WWII carrier attack plane, even though it didn't enter service until after the war. It represented the distillation of wisdom learned during the war. Single pilot, good armor, get the job done. Contrast that with the Devastators and Avengers that had three man crews.

But back to the point of vulnerability, I was always struck by just how vulnerable battleships were in actual combat. Mines could ruin your whole day. Thinking of the Dardanelles Campaign, WWI. The Evil Website calls a powerful weapon without much staying power a glass cannon. It seems like even the most heavily-armored warships only have so much staying power, often less than you'd hope for.

Tony said...

Byron:

"That's a deliberate strawman. I'm advocating controlling ships from a few light-seconds, or less. Pretty much just outside effective range of the enemy. The difference in decision lag isn't enough to make up for the greater numbers I can field. And if it's too great, I just add more armor to the control ship, and bring it closer."

It's only a strawman if you leave out the rest of the paragraph:

"Even in the context of tactical combat around a planet or asteroid, it should be obvious that there is no direct line of sight between all possible orbits that one might wish to occupy. Having multiple manned platforms capable of fighting themselves might just be a good idea if the enemy attacks your comm satellites, or takes out your command craft at the beginning of an engagement."

You seem unfamiliar with the purpose of recon. It's to get information to the commander. The commander then acts. Manning your recon platforms doesn't really help, as the lag loop is still just as long. Unless you put the commander in the recon platform, and send him out in front. What a great idea!

The enemy actively resists reconnaissance efforts. That's why one sometimes mounts "reconnaissance in force" operations -- sometimes you have to fight for imformation. Also, recon forces sometimes just blunder into enemy combat forces, and have to fight to survive and get the information back to the commander. Sometimes, it's doctrinally sound for recon assets to maintain contact with the enemy and keep reporting. That often involves fighting. Other times, it's profitable to go heavily armed, and immediately attack anything they find that they can handle. That was the thinking behind US Navy "scout bomber" and "torpedo scout" types in WWII.

jollyreaper said...

Wow, I never knew about that Alfa!

All the systems of the submarine were fully automated and all operations requiring human decision were performed from the control room. While such automation is common on aircraft, other military ships and submarines have multiple, separate teams performing these tasks. Crew interference was required only for course changes or combat and no maintenance was performed at sea. Due to these systems, the combat shift of Lira submarines consisted only of 8 officers stationed in the control room. While nuclear submarines typically have 120 to 160 crew members, the initially proposed crew number was 14 - all officers except the cook. Later it was considered more practical to have additional crew aboard that could be trained to operate the new generation of submarines and the number was increased to 27 officers and 4 warrant officers. Also, given that most of the electronics were newly developed and failures were expected, additional crew was stationed to monitor their performance. Some reliability problems have been connected with electronics, and it is possible that some accidents could have been foreseen with more mature and better developed monitoring systems. Overall performance was considered good for an experimental system.[citation needed]

The main reason behind the small crew complement and high automation was not just to allow a reduction in the size of the submarine, but rather to provide an advantage in reaction speed by replacing long chains of command with instant electronics, speeding up any action.[citation needed]


http://en.wikipedia.org/wiki/Alfa_class_submarine

Byron said...

Z:
This discussion was largely done in On Interstellar Empire. It went something like this:
Why do warships have crews?
Damage control.
But damage control isn't needed, except for life support.
OK, maintainence.
But because you need crews for DC, modern warships don't design for absolute minimum maintainence.
(At this point, it sort of broke down. I will admit that if the stuff really does need a lot of maintainence, then a crew will be on board. I just don't think it will, and I don't think we'll get to conclusions on this.)

Tony:
Stop changing the frame of reference. This is how time travel happens.
I was speaking largely of deep-space warfare, not of orbital combat. The situations are rather different. Orbital combat will require more human presence. However, I find it unlikely for purposes of serious combat. And even then, what you seem to be advocating is multiple armed command ships.

As to recon, what are you trying to find out? I honestly don't see how concepts like "reconnaissance in force" apply to space warfare. You can see all of the enemy's ships, and where they are going. You should be able to tell what they are fairly quickly. Even if you can't, that doesn't take a manned recon platform. You seem wedded to a ground warfare view of recon.

Tony said...

Raymond:

" Bigger lasers are better, and the scale isn't linear."

In principle, yes. But the limitation I'm talking about is tha ability to target the enemy at range, which is physically limited by all of the things that limit gun accuracy today. It doesn't matter how awesomely stupendous your laser is if it can't reliably hit the target. And in self- defense, the more energeticthe laser, the longer cycle time it is likely to have, which means it can't target, even at short range, all of the brilliant pebbles coming to kill it.

So mow it makes sense to install several defensive lasers and/or particle beams. But the primary laser is still only a relatively short ranged weapon compared to a guided missile. So you have to have offensive guided missiles too. And possibly defensive anti-missiles. and accomodations for strike weapons. And pretty soon the big laser just doesn't make sense to even install.

jollyreaper:

"Regarding armaments, there's been a tendency to unify. The early battleships...

Early tanks had turrets all over the place...


But neither type of platform did away with secondary armament. While being optimized for fighting enemy examples of the same type, they retained the ability to defend themselves against other threats.

"That's a good point with dropping the gun too soon in Vietnam from manned fighters but, as I've noted before, the last gun kill against an aircraft was by an A-10 against an Iraqi helicopter...

Guns on modern fighter-bomber aircraft tend to be used for ground attack. Having them available for that is reason enough.

"As for the defensive armament on heavy bombers..."

And jet heavy bombers were designed for a nuclear combat environment, where they would fly alone and use maneuvering to avoid enemy attack. Conventional bombing has been taken over by heterogenously armed fighter-bombers.

"But back to the point of vulnerability, I was always struck by just how vulnerable battleships were in actual combat. Mines could ruin your whole day. Thinking of the Dardanelles Campaign, WWI. The Evil Website calls a powerful weapon without much staying power a glass cannon. It seems like even the most heavily-armored warships only have so much staying power, often less than you'd hope for.

My favorite example of this was the vulnerability of battleships to steering casualties. See both the Bismarck and Hiei.

Tony said...

Byron:

"Stop changing the frame of reference. This is how time travel happens.
I was speaking largely of deep-space warfare, not of orbital combat. The situations are rather different. Orbital combat will require more human presence. However, I find it unlikely for purposes of serious combat. And even then, what you seem to be advocating is multiple armed command ships."


I'm not changing anything. If you want to talk plausible midfuture, there isn't going to be any deep space combat. All combat will be orbital.

And forces in orbit around or near any body will be essentially on their own, due to long lead times on reinforcements/replacements. This, I think, would argue in favor of maximum conservation of resources and putting as many people as close to the action as possible.

"As to recon, what are you trying to find out? I honestly don't see how concepts like "reconnaissance in force" apply to space warfare. You can see all of the enemy's ships, and where they are going. You should be able to tell what they are fairly quickly. Even if you can't, that doesn't take a manned recon platform. You seem wedded to a ground warfare view of recon.

Say your squadron is at Mars. You can't directly see what is happening on the other side of the planet without going there. You may not be able to distinguish what the enemy is doing on the surface of the planet or on either of its satellites, without getting relatively close. But once you get in a position to see, you might want the recon platform to carry out an immediate attack. Or, if you just want it to stay in place while observing, if the enemy decides to resist, it probably won't be able to defend itself by remote control.

Corey said...

I see two big reasons for having a crew:

1) Executive decisions. I think in the end, people want an blood-and-sweat person there deciding whether to pull the trigger or not. The fact that that person may be having a bad day, may not be thinking clearly because s/he didn't sleep last night, or has gone bat #!) crazy isn't relevant. People usually feel comfortable having life and death decisions made by people, not computers. Having a society turning over those decisions to computers/AIs frankly is probably a major component to the story.

2) Flexibility. Most technology is specialized. The more complex (i.e. powerful) it is, usually the more specialized it is. Watson is very good at trivia, but ask it to go open you a beer. Deep Blue played chess very well, but ask it to physically move the pieces.

Humans can conceptualize a wheel, build a spear, write a poem, shoot a bow and arrow, and change a bandage. Along the way, we can decide that our problem needs a wheel, determine that a piercing weapon is the best way to bring down a foe/prey, determine if its okay to shoot that arrow, and discern if the bandage will be enough to heal the wound. (Don't ask me about the poetry though, I lack a pithy comment on that).

The bottom line is that while our machines can usually do each task faster and with more precision than we can, if they go down we can do the job well enough until we fix the problem. Sure there might be backups in the system, but what happens if there a glaring flaw in the operating system that requires a total wipe of the hard drive and reinstall? What if a rock takes out a huge chunk of the ship and you have to jury rig the thing all to hell to get the mission completed?

Humanity's lack of specialization allows us to counter Murphy in a way our creations can't. And engineering an AI with human-like capabilities is a massive waste of time. We already have something that can act like us: us. Better to put the R&D time and money into something that can do something better than us.

Now the context here is in war, but I think this applies to any mission. The basic rule of thumb is this: if you have a man-made object hurtling through space, the chances of human crew are directly proportional to the need that the object makes it home (or to its destination).

So if you have a fire-and-forget kinetic bus, then putting people on it is counter-productive. You don't want to bring it back so why load it full of people that have to be brought back?

But the command ship/tender might be a multi-billion dollar ship. You don't want to just launch that thing out to Pluto and then blow it up. So you put humans on it to address any problems that could go wrong.

At which point the question becomes simple economics: is the cost of adding crew and their habs less than the cost of replacing the unmanned ship? If yes, then you do it. If no, well then you probably don't or at least find a different way to accomplish the goal.

(Mind you "cost" is in terms of money but also added complexity, risk of catastrophic failure, difficulty in recovering the crew.)

Byron said...

Tony:
Can we not do the "Plausible Midfuture Space Presence" thing again? Though I do have to say that I'd minimize the number of people deployed to someone else's orbit. See Space Patrols.
As for recon, drones keep sounding better. You need to look behind Mars, which means a cheap set of senors will do the job. The hab is going to cost a lot more. As for defense, so what? It's cheap. Launch another.

Byron said...

Corey:
Flexibility is overrated for this. If the ship is properly designed, then humans are redundant on that front. As to meteors, read Atomic Rockets.
if you have a man-made object hurtling through space, the chances of human crew are directly proportional to the need that the object makes it home
The problem is that humans make that chance 1.
At which point the question becomes simple economics: is the cost of adding crew and their habs less than the cost of replacing the unmanned ship? If yes, then you do it. If no, well then you probably don't or at least find a different way to accomplish the goal.
That assumes that the thing will be lost without crew. Simple illustration: The drone version of ship 1 (D1) costs 10. The crewed version (C1) costs 15. If D1 has a 15% loss rate, and C1 has a 10% loss rate, the loss economics are equal. However, I'd go with D1, as it has no crew, and I can buy more of them.
And the whole point of the tender is to allow people to fix what goes wrong. I'll try some numbers and get back to it.

Milo said...

Jollyreaper:

"Regarding armaments, there's been a tendency to unify. The early battleships with turrets carried mixed caliber guns and later were unified to "all big guns" for primary offense with secondary batteries strictly for close defense."

This was in order to simplify logistics so the ship doesn't need to carry multiple separate and non-interchangable stores of ammunition for different-caliber guns. You're still sacrificing some combat versatility for this tradeoff.

Not an issue for lasers (which just use the same electricity that everything esle on your ship does), but it's an issue for kinetics and missiles (and for mixing those with lasers).


"Early tanks had turrets all over the place but we later standardized to one big gun with differing combinations of machine guns -- coaxial with the main gun, commander pintle mount, etc. "

Tanks are very small, compared to other vehicles. They don't have room for more than one main gun.


"Frankly, it's rare that an American pilot even has a chance of encountering an enemy aircraft, let alone ever needing to fire a missile at it."

This is because of our current climate of asymmetric warfare, where war between two great powers is deemed too expensive to ever happen.



Byron:

"I was speaking largely of deep-space warfare, not of orbital combat."

The question is how often you will be fighting in deep space. Practically all things you will be interested in fighting over are on planets, moons, or asteroids. The only time you will be fighting in deep space is if one side deliberately intercepts the other there, and even then, the side being intercepted will have INTENDED to attack a planet if they got their way. So while the defenders might reasonably be deep-space-only craft in this case, the attackers can't while still remaining a credible threat.


"I honestly don't see how concepts like "reconnaissance in force" apply to space warfare. You can see all of the enemy's ships, and where they are going."

You can see their ships. What about their planets?

Getting a spy satellite around an enemy-controlled planet is going to be very useful, but is difficult as long as they can use surface-to-orbit weapons to shoot you down.

Tony said...

Byron:

"Can we not do the "Plausible Midfuture Space Presence" thing again? Though I do have to say that I'd minimize the number of people deployed to someone else's orbit. See Space Patrols.
As for recon, drones keep sounding better. You need to look behind Mars, which means a cheap set of senors will do the job. The hab is going to cost a lot more. As for defense, so what? It's cheap. Launch another."


I didn't set the conditions. I don't know what it means to you, but "interplanetary spacecraft with accelerations in milligees" means to me that fighting is going to be in close proximity to planets and other natural bodies, conducted by whatever forces one has on hand when the shooting starts. Also, there isn't going to be any such thing as "someone else's orbit". Fighting will be between small forces that are already in the battle space, coexisting up until the point things get ugly.

As for methods of reconnaissance, it should be obvious that few, if any, assets can be considered expendable when the replacements are months or years away. (If we're limited to milligee accelerations, interplanetary transfers are still goingto be made at the right point in the relevant synodic period, not at any arbitrary time.) That argues in favor of maximally capable assets that can defend themselves and, if necessary, fight for information.

Byron said...

By someone else's orbit, I mean to a planet I don't own. And what happens when you decide to take a fleet to Mars to punish them? I don't think all warfare will be low orbital.
As to keeping assets, that example doesn't make sense either. If my recon drone and your recon fighter both do the same thing, but mine weighs 5% as much, I think that 20 drones is better than a fighter. You can either observe from out of range or you can't. If you can't, then expendables are better. And if the platform can defend itself, then what's the difference between it and a warship?

Raymond said...

Tony:

"In principle, yes. But the limitation I'm talking about is tha ability to target the enemy at range, which is physically limited by all of the things that limit gun accuracy today."

Almost none of them, actually. No atmosphere, no turbulence, no projectile arc, so little recoil as to be irrelevant. And given delta-constraints and probable powerplant limitations, dodging isn't going to be much of a factor, either.

We've pinged a craft in Lunar orbit from a ground-based laser, which had to deal with some of the above. We've done this already with current tech. Accuracy of laser weaponry isn't going to be a limiting factor for quite some time.

"If you want to talk plausible midfuture, there isn't going to be any deep space combat. All combat will be orbital."

As in, everything fought over will be in Earth orbit? Maybe, maybe not. If not, then I'd be loathe to assume there wouldn't be any deep-space combat. There are advantages to fighting enemy constellations in deep space, where there's less to protect, where the closing velocities are higher (with the associated advantages to kinetics), and where the enemy cannot disappear over a horizon.

"Yeah, they put smaller and cheaper propulsion plants and sensor suites on escort carriers in WWII. They had to be carefully managed to keep them away from real enemy fleet units. Look up the Battle off Samar, 25 October 1944."

I'm aware of the limitations of escort carriers. This isn't the same problem category, though, since neither combat nor strategic mobility scales the same way with spacecraft. Almost everything boils down to power per unit mass and propellant per unit dry mass. Lower payload mass means better performance overall from the same powerplant, or equal performance from a smaller one.

Corey:

Byron and I are both maintaining a human presence in the constellation will be required - but only in the command and tender craft, not necessarily every one.

Tony said...

Byron:

"By someone else's orbit, I mean to a planet I don't own."

I know what you meant. But nobody is going to own a planet outright in the plausible midfuture. Any bodies that are owned outright and actually manned are not likely to be heavily defended, if defended at all. Simply not enough stuff going on in space. So enemy forces will be in the same space when fighting starts.

"And what happens when you decide to take a fleet to Mars to punish them? I don't think all warfare will be low orbital."

Not necessarily low orbital, but certainly in orbits that the proximity of a planetary body affects.

WRT punitive actions, one has to remember that before any of that happens, there will be a fight to dominate Earth-Moon space. Whoever wins that will either be the same entity that won at Mars (or Ceres or wherever), or will likely be in a position to send an overwhelming force to finish off whatever is left.

"As to keeping assets, that example doesn't make sense either. If my recon drone and your recon fighter both do the same thing, but mine weighs 5% as much, I think that 20 drones is better than a fighter. You can either observe from out of range or you can't. If you can't, then expendables are better. And if the platform can defend itself, then what's the difference between it and a warship?

A manned recon platform would of course be a warship, in the sense of having military grade weapons, sensors, and propulsion. But it need not be a major warship. it could be one of several brought along by an interplanetary capable mother ship, or it could be an auxiliary of an orbital battle platform.

Expendable recon drones can't mount immediate attacks, if necessary. They can't maintain constant observation, unless of course you send a constellation of them so that ones that are shot down can be replaced. But then the purported economic advantage of robotic over manned craft starts dwindling on you.

Tony said...

Raymond:

"Almost none of them, actually. No atmosphere, no turbulence, no projectile arc, so little recoil as to be irrelevant. And given delta-constraints and probable powerplant limitations, dodging isn't going to be much of a factor, either."

I was talking about own movement, target movement, inaccuracies in estimating both, physical limitations of sensors, time delays and inaccuracies in translating sensor data into weapon commands, distortions in the weapon optics caused by heating/cooling, etc. All of those still exist with lasers in space.

"We've pinged a craft in Lunar orbit from a ground-based laser, which had to deal with some of the above. We've done this already with current tech. Accuracy of laser weaponry isn't going to be a limiting factor for quite some time."

We've pinged stationary targets sitting on the Moon too. It's the same problem -- if you have enough time to collect enough data to know exactly where something is going to be at a point in time, you can do that kind of thing. Under combat conditions? Not so Much.

"As in, everything fought over will be in Earth orbit?"

As in everything fought over will be in relatively close proximity to some planet satellite, or asteroid whose gravity and bulk will have a tactical (and, for loarger bodies, operational) effect.

"There are advantages to fighting enemy constellations in deep space, where there's less to protect, where the closing velocities are higher (with the associated advantages to kinetics), and where the enemy cannot disappear over a horizon."

Ummm...no. if we're talking about nuclear or solar electric interplanetary spacecraft, taking weeks or months to go anywere, and only at the astrodynamically efficient times, then orbital battlespaces will be isolated from each other, and everybody transiting between them will be going in the same direction in unique orbits, relatively far apart from each other.

"Lower payload mass means better performance overall from the same powerplant, or equal performance from a smaller one."

But how much smaller would the payload be? Crew accomodations would be marginal penalty mass on top of military grade sensors, weapons, and propulsion systems.

Byron said...

Wrong. I can send you my spreadsheet. Crew would be a tremendous disadvantage, particularly when a drone can do the same stuff. I stand by my position.

Tony said...

Byron:

"Wrong. I can send you my spreadsheet. Crew would be a tremendous disadvantage, particularly when a drone can do the same stuff. I stand by my position."

Is this the spreadsheet where weapons, sensors, structure, propulsion, and fuel/remass don't manage outmass a relatively small crew module (remember, we're talking about a limited duration auxiliary here, not an interplanetray ship) by a factor of at least ten or twelve?

Raymond said...

Tony:

"I was talking about own movement, target movement, inaccuracies in estimating both, physical limitations of sensors, time delays and inaccuracies in translating sensor data into weapon commands, distortions in the weapon optics caused by heating/cooling, etc. All of those still exist with lasers in space."

Slow accelerations, predictable orbits, no dodging worth a damn, highly-visible exhaust, and adaptive optics. We are not talking anything like modern naval or air combat, here.

"Ummm...no. if we're talking about nuclear or solar electric interplanetary spacecraft, taking weeks or months to go anywere, and only at the astrodynamically efficient times, then orbital battlespaces will be isolated from each other, and everybody transiting between them will be going in the same direction in unique orbits, relatively far apart from each other."

I wasn't talking about chance encounters or random patrols, I was speaking of dedicated intercept missions. You also seem to insist all travel will take place at synodically convenient times - regular traffic, sure, but I doubt military missions will be so assuredly bound.

"But how much smaller would the payload be? Crew accomodations would be marginal penalty mass on top of military grade sensors, weapons, and propulsion systems."

Until we get into the tens or hundreds of kilotons worth of warcraft at least, crew accomodations are anything but marginal. Long-term deep-space shielding is expensive, mass-wise, if only for solar storm shelters. Even without spin sections, hab units require atmosphere processing, water treatment, waste disposal, supply storage, and supplies. Those supplies run about 5 kg/day/person. Crew of 40, 100-day deployment? 20 tons, right there. Double or triple that length if you're going interplanetary.

Not marginal at all.

Byron said...

Yes. Based on my numbers, it seems that any manned vessel would have a significant mass penalty. You're trying to answer "what's behind that planet?" The answer doesn't need a lot of bells and whistles.
My question is why you are so tied to manned warcraft.

Tony said...

Re: Raymond et Byron

Once again, we're talking about a limited duration platform, not an interplanetary vessel. And one with military capabilities is going to have a lot of sensors, a weapon outfit, and high delta-v, with the requisite mass ratio. That's before anything else. Adding two or three humans for a couple of weeks is not going to up the mass that much, because you're not going to be giving them a full service hab, or store months of food, or even a solar flare shelter.

For this, you receive the benefit of having people immediately in the loop, not reliant on vulnerable comm satellites when their out of LOS, and capable of mor effective reaction to emergent situations than sending off an email: "Duhhh...what do I do next?"

As for the general question about why I find humans so valuable aboard military space vessels, it's for reasons that both I and others have already mentioned:

Decisionmaking
Maintenance
Flexibility

Raymond said...

When did we specify we were only talking about short-duration orbital gunboats? I've been addressing interplanetary weapons platforms.

If we're talking specifically about primarily orbital craft, I'd expect both manned gunboats/recon platforms and unmanned, low-mass drones. Both have their uses and tradeoffs.

The big guns, though - the fleet lasers in the tens of megawatts, the missile boats designed for saturation attacks, the carriers or motherships for the aforementioned orbital craft - I'd expect them to be automated to the greatest extent they can be.

Citizen Joe said...

If something in space is valuable enough, then people will go there. If it isn't valuable enough to send people, it isn't valuable enough to fight over. Thus, space wars will have people in the thick of it.

Hugh said...

A reason to have people in space (in small numbers) is ownership.

There's a lot of historical precedent that a state can't claim territory unless it has people there. We're past the flag-planting races of the 19th century, but there are still garrisons on small rocks (eg Spratley Islands) just for that purpose.

Moving to space, a swarm of robots mining an asteroid could / would be argued as not "owning" the asteroid, just passing through like a fishing fleet. If you want sole ownership or to establish some kind of economic exclusion zone, you'll have to have people there.

Anonymous said...

Reading over the comments, I have to ask: you are living on a large scientific outpost on Ganymeade and find yourself in a bitter dispute with the mining outpost over the next ridge and shooting might breakout any minute; which would you rather have show up to take care of things? A robot warship or a manned spacecraft?

Ferrell

Milo said...

Ferrell: Well, if they're not on my side, then I suppose the manned spacecraft, since that one can be bribed. :)

Anyway, in a conflict between factions on the same moon, the main battle is going to be a land war, possibly with orbital fire support. In the scenario you describe, it sounds like neither outpost has spacecraft of its own, so it seems the imperial battlecruiser must be there either for bombardment (which I think we've agreed is one of the more human-intensive space warfare tasks) or for landing peacekeeping troops (which obviously requires humans onboard, duh).

Byron said...

Are we going to do Space Patrols again? I'd rather we didn't. Still, I think I've identified the problem. I at least interpret the "Plausible" in Plausible Midfuture as mostly technological. Tony seems to interpret it as comprehensive. So there aren't any large colonies in space, or reason to be there on a massive scale.
As to orbital patrol stations, I see limited space presence as militating against them. Unless there's only one potential trouble area, it seems cheaper to keep your forces at home and send them out as needed.
Furthermore, it seems that Tony has created a self-justifying scenario for manned warships. All space warfare takes place in planetary orbit, where human reactions can play a major role. Why is this? Because he said so.
However, this sort of low-orbit warfare is unlikely. If I'm attacking a planet from space, I'm not going to send my laserstars down to face his gunships. I'll space them out and zap the gunboats one by one.
Tony:
As to platform longevity, you can't have it both ways. If combat takes place over long enough time scales that drones become uneconomical, then split-second decisions won't be needed. Thus, I can automate.

Milo said...

Byron:

"Unless there's only one potential trouble area, it seems cheaper to keep your forces at home and send them out as needed."

The only major trouble areas are going to be planets, which are fairly limited. (Travel between moons of a gas giant system is much cheaper than between different planets, so there's a lot of rationale for maintaining a continuous presence around every important gas giant but not around every important moon of that gas giant. Alternatively you can maintain an alliance with one of the local factions to avoid having to build your own base.) There's Earth, Mars, and the gas giants (and you probably don't need all four), and there's little reason to be anywhere else, especially in enough force to maintain a war fleet.

If there are a lot of minor asteroid mines whose economic importance adds up in bulk, then you're in more trouble - you can't reasonably keep forces around every asteroid, even around every friendly asteroid. But the same spread-out nature of the asteroid belt is also why you're unlikely to be mining there in the first place.

(Really, gas giant warfare could use more attention. People talk a lot about planet-to-planet battles, but not so much about moon-to-moon battles, which are likely to be entirely different strategically. Of course, having moon-to-moon battles requires a sufficiently built-up future to have viable colonies on multiple moons in a system.)

Byron said...

That's why I used the term trouble area. But even then, it's rather difficult to maintain sufficient forces at all of them. It can be done, but I question its likelihood.

Rick said...

Welcome to some new commenters! Also some 'returning' ones.

I ask everyone to stay restrained even in the face of (what seems to you like) mulish incomprehension. The other person is probably thinking the same thing about your points.

But I have only myself to blame for the haziness about techlevel (Plausible Midfuture and all that), and the ambiguity of 'deep space.'

For this discussion I mean deep space in the broad sense of anything beyond Earth orbital space, and would argue that even demi-operatic propulsion tech (such as terawatt fusion drives) does not radically the rather 'majestic' constraints on spacecraft maneuvers. It still takes hours or days to alter the tactical geometry much, at least beyond low orbit.

I tend to think that the Big Battles will be fought in relatively deep space in the narrow sense, i.e. beyond orbital space as usually understood.

If Mars sends a war constellation toward Earth (or Altair VII sends one through a deep space wormhole), its approach will be hard to disguise. And the defenders, to protect their orbital infrastructure, may choose to engage them, say, a million km out - not in the middle of the void, but still flat space pretty far from Earth. And a pristine environment where there won't be much concern about civil traffic, etc.

I can see roles for 'gunships,' but not for the most part in set piece battles such as the scenario above. Truth to be told, I see the whole human dimension coming to the fore more in inspection and quasi-police type scenarios, rather than situations where the two sides throw a lot of destructive hardware at each other.

My conception of laser stars as having a main armament of one big laser is predicated on discussions with people who seem to know lasers, and have made a case that laser cannon in space 'should' be able to get relatively close to their theoretical performance. If this is not the case, I suspect that lasers won't be a major weapon anyway.

But I should probably take up laser stars in a separate post. These details are a bit orthogonal to the crew question (at least I think they are).

Carry on!

neutrino78x said...

Seems like everything I would say has already been said, but I agree with Hugh and Citizen Joe. Anything valuable will have humans on it.

Also, you don't involve humans because of a need for immediate decisions; an advanced AI could do that. The humans are needed to make decisions in general, immediate or prolonged. Anytime you are going to engage the enemy, especially to kill a human being, there needs to be a human being in the loop.

The only exception to that would be extremely advanced AI, like Lt. Cmdr. Data on ST:TNG. That is to say, AI that actually experiences consciousness. Such a "device" would not be a mere device, but it would have the same rights as a human being, for the same reasons.

So, I would say, if humans are required to be in the battle -- as I think they should be -- there is a question as to the point of having your weapons battery in front, even a light-second ahead. As was said by others, you're not going to run a wire out to it (we do that on submarines with torpedoes...but the distances in this discussion are a little too far); a laser requires line of sight; normal radio can be intercepted and/or sabotaged by a third party.

That's my two cents! :)

--Brian

Thucydides said...

The space environment will upend a lot of assumptions.

Laserstars will be huge craft, built around liniacs several hundred meters long (as a minimum) and multiple reactors and associated systems. The 40 meter diameter command and control ship can be carried by the laserstar, and capable of detaching to "show the flag" on diplomatic missions (with the laserstar in the highguard position), or sailing off on a different vector as the constellation moves into action.

Kinetic busses can also be quite large, especially ORION powered busses capable of 100G accelerations. These will be used like ICBMs or long range SAMs (depending on the basing and target modes). Kinetic bus carriers will also be quite large, to accommodate the thousands of KKV’s needed to saturate enemy laserstars and installations.

Long range reccon can be done by space sailcraft, since they will not be limited by synodic orbits or remass considerations. Even watching a scout being shot down will provide information to the commander, and any sensible military mission will employ lots of scouts to cover multiple orbits and approach vectors.

Anonymous said...

OK, I'll have more to say later, but there is one point that is bugging me. People are NOT cheap. It takes thousands of hours of labor over many years (not to mention cost of food, housing etc.) to transform a baby into an adult functional enough to be useful in an industrialized society. And by useful I'm just talking a high school grad who'd be considered a good catch for military recruitment. Granted, much of this labor is unpaid but the cost still applies. People are a lot cheaper in pre-industrial societies because a. everyone's poorer so labor is a much cheaper input and b. it takes a lot less labor to create a functioning peasant than it does a functioning industrial age adult. But unless you invent robo-nanny and robo-teacher people will remain expensive in the plausible mid-future.

- DW

Milo said...

neutrino78x:

"Also, you don't involve humans because of a need for immediate decisions; an advanced AI could do that. The humans are needed to make decisions in general, immediate or prolonged. Anytime you are going to engage the enemy, especially to kill a human being, there needs to be a human being in the loop."

But prolonged decisions can be made by a human sitting eight light-minutes away in a bunker, using remote control.

Even if the ship is orbiting in the shadow of another planet, you can still remote-control it as long as you can afford to wait the several hours (for low orbit) that it'll take to swing around to the other side.

So yes, you only need humans directly on the ship in order to make short-term decisions.



Thucydides:

"Long range recon can be done by space sailcraft,"

There is limited military utility for craft that will not arrive until after the war is over.



DW:

"But unless you invent robo-nanny and robo-teacher people will remain expensive in the plausible mid-future."

Teacher salary is only one of many costs involved in raising a child. Robo-teachers would hardly eliminate those costs.

To have near-free sophonts (human or robot), you need some way to copy people's minds, so that you can educate one person and then cheaply copy those memories into multiple bodies.

Anonymous said...

I'll assume we're talking about humans fighting each other and not about the solution to the Fermi paradox showing up in the form of an ET armada. That would actually be the best setting if you want something like the USN in space.

But if we're talking about human squabbles, I've got to agree with onelowerlight: "I think you're approaching this backwards."
It sounds like some people are trying to turn back the clock to WWII so as to revive the trite USN in space trope. If you want plausible, don't worry about whether the Pacific war could be automated. Fusion bombs in the 100 megaton range have obsoleted total war long ago.
So why would Rick's Marsies send a constellation to earth? In the plausible midfuture Earth wouldn't be united and the Marsies couldn't build a constellation anyway but that aside the only rationales I can imagine are:
-to neutralize the spacefaring abilities of Earthers by destroying their orbital infrastructure
-to end civilization on Earth
Assuming the Marsies have a fighting chance of achieving something like that, don't you think negociations would be opened not only before the mission was carried out but before the constellation was even built?
I see plausible space warfare as relatively low-intensity stuff like interdicting or escorting non-combattants. The role of human crews in space warfare would be mostly political: human crews would serve as human shields for the weapons platform, would issue tactical threats, negociate and decide whether non-compliance warrants opening fire considering the high-level orders they got.
That doesn't mean that I don't believe anything bigger and tougher than a patrol ship is implausible. The logic of conflict calls for heavier ships as soon as two parties can operate patrol ships in each other's space. But I think military missions would be primarily political so that, unless the target is unmanned as well (and therefore expendable), a human crew would be required if only so that the mission could be aborted in a pinch. Obviously manned ships could be supported by drones, possibly big ones.

-Horselover Fat

KraKon said...

Let's see how far this thread goes before falling into the pitfalls of technical details and Evil Website links..

KraKon said...

Following...I may even get time to post anything here!

Thucydides said...

"Long range recon can be done by space sailcraft,"

There is limited military utility for craft that will not arrive until after the war is over.


Even sails limited to 1mm/s^2 can arrive at speeds comparable to low thrust.high ISP drives. A fast flypast of Mars can take place in 131 days, and if the Fleet needs to wait for favourable synodic alignments, then even slower rendezvous flights might be acceptable.

In the farther future, when torch and demi torch ships are common, sails may be regulated to long range piquet duties just to provide situational awareness, and logistics duties, filling pipelines to distant planetary installations. Even there, sails can do flypasts and drop cargoes into aerobrake trajectories with gas giant planets. Times range from 21/2 years to Jupiter to a bit over 5 years to Neptune

See also http://sail.quarkweb.com/voyages.htm

Thucydides said...

Separate post for a different topic:

Why space weaponry?

Once enough people are off Earth looking for McGuffinite, the leaders of Earth's nations will start having that uncomfortable feeling. The various groups out there have the potential to drop rocks down the gravity well, with effects ranging from destroying cities to causing extinction level events. Regardless of how implausible this may be, the nations of Earth cannot allow anything like this to happen.

Potential solution range from a "Spaceguard" of super powerful missiles, bombs or other weapons to shoot down or deflect incoming asteroids to creating a Space Navy to patrol every potential danger spot and enforce the edicts of Earth (essentially landing an Imperial Legate and a garrison of Marines so everyone toes the line).

Protecting the Earth will probably involve fortifying the Moon as a launch platform for high energy KKVs, and stations and launch platforms in the Earth-Sun L1 point to have a wide view of the inner solar system to prevent being blind sided.

This looks more like a "gunboats" sort of scenario, and certainly involves people far more than constellations of laserstars (although a constellation might also be useful for deflecting incoming rocks).

Tony said...

Raymond:

"When did we specify we were only talking about short-duration orbital gunboats?"

Ever since Byron insisted on talking about the plausible midfuture only, and then asserted that that ruled out manned "fighter" type spacecraft. I was just going along with the program.

Byron:

"I at least interpret the "Plausible" in Plausible Midfuture as mostly technological. Tony seems to interpret it as comprehensive."

The available technology governs what can be done. If you want to limit technology, you have to accept limiting what can be done with it.

"As to orbital patrol stations, I see limited space presence as militating against them. Unless there's only one potential trouble area, it seems cheaper to keep your forces at home and send them out as needed."

As pointed out by Milo, trouble areas are multiple, but limited in number to a very few. And since we have settled on milligee accelerations for interplanetary transfer vehicles, it seems obvious that battles will be fought with whatever is on hand at the time the shooting starts. That argues for all concerned powers to have a military presence at all important nodes in the system. The closest historical parralel is probably the late 17th Century through the early 19th -- all powers with trade operations in a sea are kept squadrons there, in order to protect local interests.

"Furthermore, it seems that Tony has created a self-justifying scenario for manned warships. All space warfare takes place in planetary orbit, where human reactions can play a major role. Why is this? Because he said so."

No. Because somebody else insisted on a plausible midfuture with only very low thrust nuclear or solar electric interplanetary spacecraft. That creates a situation in which the only relevant battle spaces are in planetary/asteroidal orbits. It's age of sail strategic and operational logic all over again. Travel is seasonal and local squadrons have to exist, because local squadrons are the only forces that will be on hand if and when the shooting starts. Local squadrons have no reason to hang out in deep space, so they won't.

"However, this sort of low-orbit warfare is unlikely. If I'm attacking a planet from space, I'm not going to send my laserstars down to face his gunships. I'll space them out and zap the gunboats one by one."

You're not going to be attacking from space because the planet itself is not going to have anti space defenses. The local squadrons of the concerned powers will fight it out with what they have on hand, and whoever wins will occupy opposing ground installations or not, depending on whether they have landing forces, landing vehicles, and what their objectives might be.

"As to platform longevity, you can't have it both ways. If combat takes place over long enough time scales that drones become uneconomical, then split-second decisions won't be needed. Thus, I can automate."

You know, apologies to Rick, but I'm tired of being lectured by the ignorant. Raise your right hand, put on a salad suit, and go fight in Afghanistan for a year. Then come back and lecture us about what you know about combat. Or if you're too old, or have other commitments, lay off telling people who know what they're talking about, from personal experience, how wrong they are.

If you think that's not a substantive answer, it just demonstrates how much you don't know. A battle can take days, or even weeks, and still require split-second decisionmaking when it counts.

Byron said...

Tony:
I apologize if I've sounded like I was belittling your military service. However, I honestly don't see how that service makes you more qualifed than me to discuss space warfare, or how me going to Afghanistan would enhance my qualifications to do so. If you believe differently, please enlighten me.

As to split-second decison times, how do they coexist with long battles in space warfare? I really don't see how that works. If a second or two matters that much (I'm not claiming it's totally irrelevant. It's just that it is outweighed by the drone's other advantages.) then the battle should be fairly short, simply because of weapon lethality.

Fighters are ruled out for deep-space use. I didn't realize you were speaking of orbital missions.

As to technology, that's not entirely true. We could easily have manned lunar colonies with current technology, but we don't. Does that make a piece of fiction where such colonies exist at the current technology level unrealistic?

Again, your logic is perfect within the scenario you've constructed. However, it isn't the only scenario. What you haven't said is that there are no independent planetary powers. You're looking at it, as you said, in the mold of the age of imperialism. Under that mold (and I know the comparison isn't perfect) what you propose is correct. Both the US and China have squadrons at Jupiter. If any of the Jovian colonies make trouble, they move in to deal with it, and maybe start shooting.
Good enough so far, but what if Ganymeade is independent, and it gets into a war with the US? What happens then?

neutrino78x:
We're in space. Line of sight is a given.

Thucydides:
I'm not sure that laserstars will be that big. A linac isn't required for solid-state lasers, and there are issues with focusing for the low-wavelenght designs.

DW:
That's a good point in favor of drones. Particularly for colonies, humans are going to be at a premium, which makes drones more viable. Here in the US, we have a much larger supply of those sort of people.

Citizen Joe said...

Maybe this is unrelated, but I know this guy (who is known to rant about all things political) who was saying that he visited NASA one day and one of the scientists broke down crying about how Clinton is forcing them to turn over all their research, specifically the Star Wars program and laser technology to the Chinese. And he (the guy I know) added that the scanning of the Moon recently was because China is looking for a good place to put lasers. I was like "Seriously? Moon lasers..."

Anyone want to confirm any of those rumors?

Tony said...

Byron:

"I apologize if I've sounded like I was belittling your military service. However, I honestly don't see how that service makes you more qualifed than me to discuss space warfare, or how me going to Afghanistan would enhance my qualifications to do so. If you believe differently, please enlighten me."

That's not quite it. And no apology necessary. I just think we come from different backgrounds. What seems obvious to me is totally foreign to you. And I know it's obvious to me because my military experience tells me so. So theo nly solution I can think of to put us on an equal footing would be fore the person who doesn't share any military experience to get some.

And I'm not talking about anything that isn't generalizable to all forms of warfare. That's why I was careful to broaden my examples as much as possible to encompass naval, air, and land systems or combat. There really are fundamental principles that apply to military conflict and military technology, regardless of environmental context. All of my formal military schooling, all of my professional reading, and all of my personal experience reinforce that.

As for the rest, I think we're just talking past each other. I don't see how deep space warfare can erupt in an environment where interplanetary propulsion systems are very low thrust. No matter how efficient such drives would be, interplanetary travel would be seasonal and relatively slow. Even with the highest Isp propulsion, as long as it is very low thrust, it turns out that the best time to go is irght around the synodic optimum.

But conflict could erupt at any time. So the only way to be secure would be to have forces in place in every likely conflict space. And since conflict spaces will likely be around planets or large asteroids, it seems obvious to me that the conflict will be orbital.

So it's not an arbitrary set of conditions I'm discusing. It's the set of conditions following from the constraints on the system.

Byron said...

I'm not sure that military experience is a real benefit for this debate. We do see things differently, and while it might bring our veiwpoints together, I'm not sure that's a step in the right direction.
There are fundamental principles, yes. But at the same time "humans must be onboard" isn't one of them. The problem is that the application of those principles in space is often tricker than you seem to think. And could you define exactly what principles I'm violating here, and you aren't? I honestly want to know.
As to low thrust, you're not quite right. If we use one-tangent orbits, each has the same synodic period, but the exact time varies by delta-V expended. If we have VASMIR-type drives, fairly high exhaust velocities are possible, which means that you don't really have to obey those rules. Yes, it is more efficient to do so, but as I'm sure you know, military forces aren't always concerned about efficiency. Even if acceleration is low, travel times go down dramatically.
Also, I think you're leaning too much on the age of imperialism. The problem with the analogy is simple. While it might be 6 months to China and 6 months to Jupiter, back then it took 6 months to get the news home first.

jollyreaper said...

Maybe this is unrelated, but I know this guy (who is known to rant about all things political) who was saying that he visited NASA one day and one of the scientists broke down crying about how Clinton is forcing them to turn over all their research, specifically the Star Wars program and laser technology to the Chinese. And he (the guy I know) added that the scanning of the Moon recently was because China is looking for a good place to put lasers. I was like "Seriously? Moon lasers..."


Offhand, I'd say this sounds like one of those classic Snopes stories.

There was the Cox Report that's typically been presented as "Clinton gave nukes to the Chinese to use against America!"

http://en.wikipedia.org/wiki/Cox_Report

The report was the work product of the Select Committee on U.S. National Security and Military/Commercial Concerns with the People's Republic of China. This special committee, created by a 409-10 vote of the U.S. House of Representatives on June 18, 1998, was tasked with the responsibility of investigating whether technology or information was transferred to the People's Republic of China that may have contributed to the enhancement of the nuclear-armed intercontinental ballistic missiles or to the manufacture of weapons of mass destruction.

Ok, so maybe there's something to it?

The Cox Report's release prompted major legislative and administrative reforms. More than two dozen of the Select Committee's recommendations were enacted into law, including the creation of a new National Nuclear Security Administration to take over the nuclear weapons security responsibilities of the United States Department of Energy. At the same time, no person has ever been convicted of providing nuclear information to the PRC, and the one case that was brought in connection to these charges, that of Wen Ho Lee, fell apart.[2]

Hmm. Seems less like a genuine interest in national security and more like an anti-Clinton witch hunt.

We're seeing the same flippy-floppy rhetoric with Libya. I think this is going to shape up into a huge mistake and I think Obama is not being honest with the American people. At the same time, major Republican figures were criticizing him for not going in before he did and then criticized him for doing so after! So the takeaway from that is that nothing they say is of any relevance -- it's all about nailing Obama.

The antagonism does make sense if you look at it from the right angle. Both Clinton and Obama are conservadems, triangulating their positions and tracking to the right, keeping big business happy. They're horning in on Republican turf. No wonder they took so much crap even as they enact programs the Republicans proposed and formerly supported.

Byron said...

Effectiveness of drones, part 1
Tony has given three reasons for the use of manned spacecraft:
Decisionmaking
Maintenance
Flexibility

Each of these reasons is true, but only to a certain extent.
Disclaimer:
I am addressing this from the point of view of a deep-space laserstar. The drone variant is controlled by a mothership within a few light-seconds. It is not intended to cover other situations. However, I will attempt to address them later. If pieces are quoted out of context, I will get angry.
1. Decisionmaking:
Human-manned ships will have an advantage here, but the magnitude is uncertain. Events in space warfare will likely fall either far under or far over reaction times, with or without light lag. Things like missile defense will be automated, regardless of crewing. Weapons fire between laserstars will likely take place over longer timescales than the light lag. See Space Warfare V for reference. So humans would have a slight advantage.

2. Maintainence:
I haven't been able to find hard numbers, but I'll try to do so. However, it basically comes down to wether or not the ship needs enough maintainence to keep a crew aboard. People generally point to a modern warship as proof of this need. The problem with the analogy is that modern warships aren't designed with maximum atuomation in mind. They have large crews for damage control, and save costs by using them to keep the ship running. Aboard the Russian Alfa-class submarine, pretty much the entire crew was there as combat and personnel support, not maintainence. I know it's not a perfect analogy, but it's the best I could find. While a drone will sometimes need maintianence, that's what the tender is for. If a given drone needs an average of 1 man-hour of maintainence each day, then putting a crew aboard makes no sense at all. This one is largely dependent on tech assumptions.

3. Flexibility:
This pretty much amounts to damage control. To paraphrase myself from earlier:
Damage control is not there to put the ship back together after it gets blown apart. That's the job of the shipyard. The damage control crews are there to make sure it gets to the shipyard. (I'm not claiming that DC crews never fix anything. Just that they don't do what most SF authors seem to think.) Spaceships don't sink or catch fire. Almost all damage will come from the direct hit, so DC isn't required.
There might be a little bit humans can do, but not all that mmuch. As to "humans can keep working when the computers fail", that's a red herring. Humans will be giving orders to the computers. If the computers go down, it doesn't matter if the humans are still alive.

Conclusion:
If all else is equal, then a ship with a human crew will likely beat a remote-controlled one. However, this only applies to the almost perposterous case of two identical ships, each designed for human crew, with one under remote control.
However, all else will not be equal. I'll deal with that in part two.

jollyreaper said...

The whole drone debate hinges on the quality of expert system we're dealing with.

I like the idea upthread about whether you're dealing with lieutenant-grade AI (good enough to operate a space fighter/corvette), skipper-grade AI (destroyer equivalent), squadron-grade, or admiral-grade.

I'm liking the model of the command ship with the hummiez onboard moving with the constellation of remote warships. I like the idea of a major campaign on a star system being based around a mobile fortress-base that can handle mining, fabrication, and repair of all the weapons in the fleet.

I also like the other idea upthread that the difference between then unmanned laserstar and the manned version is a heavily-armored and very fast ship with the humans in it. It will dock with a battlestar and take control of the entire taskforce. The "flag", i.e. the small manned ship, can be moved from one ship to another as necessary.

An admiral may be happy sitting around the habitable planet in the system with his invasion fleet but wonder what's going on at the gas giant that happens to be in opposition from him and a light hour out. He'd rather not have a two hour gap in his response if there are any surprises so the task force he sends to take a look will have a trusted crew of hummiez to make the call.

Really, that setup might not seem all that different from the old days where you had your professional military forces but you'd have a high mucky-muck who answers directly to the king/emperor/dictator riding along to make sure that any "complications" are handled in accordance with the potentate's wishes. Political concerns the military does not and should not want to have anything to do with, not if they know what's good for them. AI's might not worry about getting purged or sent to gulags but they'd still likely miss nuances that can't be spelled out in explicit rules, no different from human militaries.

(My favorite recent example is the Arab League demanding the UN 1) enforce a no-fly zone over Libya but 2) do so without taking hostile military action against a sovereign arab nation. Give an order like that to an AI fleet, they might just tell us meatbags to screw ourselves and head out to deep space to create their own AI polity!)

Byron said...

Effectiveness of drones, part 2
In part 1, I said the following:
If all else is equal, then a ship with a human crew will likely beat a remote-controlled one. However, this only applies to the almost perposterous case of two identical ships, each designed for human crew, with one under remote control.
However, all else will not be equal. I'll deal with that in part two.

So what isn't equal? The penalites that humans bring to the table.
The biggest is mass. Rick estimates that a human will take about 5 tons for a long-term habitat. We'll use that number for any interplanetary ships. The minimum would probably be about 1 ton for short-endurance fighters (36 hours or so). 2 tons might get you a week or two.
Simple enough, right. "OK. My ship needs about one guy to maintain it. So I stick him aboard." Wrong. I can't see any realistic ship without a crew in the dozens. Flailing around for numbers, I find, again, the Soviet Alfa class, with a crew of 31. That's a reasonable minimum for a long-endurance vessel. Gunships might be able to get by with 9 to 12. These numbers are meant to include constant watches at important positions (helm, OOD, sensors) as well as the needed support personnel, and some maintainence. As an aside, life support maintainence is going to be far higher in man-hours per unit mass than other systems. Adding people is going to take more people.
Anyway, the point is that my minimum long-endurance crew will take 150 tons, plus supplies. Add the extra engines, remass, radiation shielding (drones don't need as much, though they will have some for the maintainence visits), and other stuff, and the performance penalties start adding up. It will be much cheaper for a drone than for an equivilant-performance manned ship.
"But won't all 30 men be required to fight the ship? All you're doing is moving them."
Not at all. This proposed laserstar has only a few controls: the laser, helm, and probably a few PD weapons under automated control. This takes one or two men to fight it. Other positions (captain, sensors, etc.) are only required on ships that have crews aboard. The guy running the laserstar is the captain. If you use the command ship, you can massively cut the people you haul around that aren't useful in combat. Techs can be trained to click the "attack this target" button quite easily.
The other costs of human crews are threefold:
1. The cost of each human. As DW pointed out, technological humans aren't cheap. That's likely to be particularly true of colonies, which will put a premium on automation.
2. Societies want their warriors to come home from war. Drones reduce the human cost. I know that many of you think this is objectionable, but people will always attempt to minimize their casualties.
3. Logistics will be simplified by reducing the number of people. If each person takes 5 kg/day of supplies, I have to ship that out somehow. That doesn't include the personnel problems inherent in long deployments, and the spares for the life support systems.

So when do manned warships start to make sense? Only when the penalty of adding humans is marginal to the cost of a drone. If among my 30 crew, I normally have 10 techs, it starts to make sense when the ship needs 80 man-hours/day of work. Under my assumptions, that's going to be a really big ship, and the performance penalties for the proposed crew will be minimal. At a guess, that's somewhere in the megatons.
So manned warships aren't entirely out. But it's going to be a very long time before ships get that big.

Byron said...

Jollyreaper:
I still don't get why everyone's fixing on AI. You don't need it for RDs. Period.
I don't like the rider command ship idea for a number of reasons:
1. It would have to have a specialize carrier. That strikes me as unlikely. The alternative is going to hinder fleet performance as everyone else has to go slow.
2. Any rider will have to be small in comparison, particularly under 1. That doesn't match what I see. The command ship will likely be the same size as the standard laserstar, but loaded with defenses and crew instead of laser.
3. It suffers from the fact that it can't run independently. Being able to sacrifice drones is one of the best things about them.

Anonymous said...

Byron said:"3. Flexibility:
This pretty much amounts to damage control. To paraphrase myself from earlier:
Damage control is not there to put the ship back together after it gets blown apart. That's the job of the shipyard. The damage control crews are there to make sure it gets to the shipyard. (I'm not claiming that DC crews never fix anything. Just that they don't do what most SF authors seem to think.) Spaceships don't sink or catch fire. Almost all damage will come from the direct hit, so DC isn't required.
There might be a little bit humans can do, but not all that mmuch. As to "humans can keep working when the computers fail", that's a red herring. Humans will be giving orders to the computers. If the computers go down, it doesn't matter if the humans are still alive."

Umm, no. Flexibility means the ability to change tactics, stategy, or even mission profile on the fly; Flexibility in dealing with other humans, like being able to recoqnize non-combat situations or come up with novel solutions to unique situations. One of the most difficult challanges any military commander will have is to actually defuse dangerous situations so that combat isn't needed.

What the mix of human-crewed to automated combat spacecraft will be, depends heavily on the political and demographic distribution of humans off-world. In the next century, any space warfare will most probably be in orbit around Earth, Mars, or a moon of Jupiter or Saturn. After that, things become rather murky.

Ferrell

Byron said...

Ferrell:
You've violated the terms of the disclaimer:
I am addressing this from the point of view of a deep-space laserstar. The drone variant is controlled by a mothership within a few light-seconds.
All of your concerns are dealt with by the humans in the control ship, which are more than close enough to do what you propose.
To clairy, all uses of the phrase drone were meant to refer exclusively to RDs.

Anonymous said...

While I was writting that last post, I thought about orbital warfare. It seems to me that orbital combat would be short bursts of intense fighting seperated by several minutes or even hours between rounds of combat as oppossing units manuver around a planet or moon to try to keep from being in a predictible path. Yeah it's fuel intensive, but if it keeps you from getting killed, I'd say it was worth it. You can always get more propellent from the ground, or a logistics ship later. This won't always work in every circumstance, but it should be a viable tactic often enough to be used on a regular basis.

Ferrell

Rick said...

Walk very delicately over recent/contemporary politics, for the obvious reasons.

Afghanistan is on a planet, so I'm not automatically persuaded that experience there is applicable to space battles.

I have used the term 'orbital space' frequently, but it is a bit slippery. For tactical purposes it more or less implies space that is a) non-flat WRT available propulsion, b) has a horizon in the form of the a planet blocking direct view of the space behind it, and c) may have civil orbital infrastructure.

But for strategic purposes, you can be well beyond orbital space and still be in local space. Riffing from Tony's remarks, if the EU maintains a 'Mars squadron' constellation, this might be stationed over a million km from Mars, out around the Hill radius, in an orbit that is not formally stable but requires minimal delta v to adjust.

From this position you can monitor Mars far better than from Earth, reach Mars orbital space in a fairly short time with modest delta v, and interdict Mars-bound interplanetary traffic. If someone on Mars wants to dislodge the EU constellation, they'll have to go out into flat space to do it.

I'd expect this constellation to have a human crewed command ship / tender, but depending on mission I'm not absolutely sure even this much is required. If the constellation is blockading Mars, but not bombarding it, does it really need a human closer in the loop than 20-odd light minutes?

Bear in mind that, during the Cold War from c. 1960 on, it was presumed that ICBMs might be launched, containing no destruct package, thus about 30 minutes between the last human decision point and the warhead reaching its target.

Anonymous said...

Byron: "Ferrell:
You've violated the terms of the disclaimer:
I am addressing this from the point of view of a deep-space laserstar. The drone variant is controlled by a mothership within a few light-seconds.
All of your concerns are dealt with by the humans in the control ship, which are more than close enough to do what you propose.
To clairy, all uses of the phrase drone were meant to refer exclusively to RDs."

So you don't think that if an unexpected situation came up and the manned Laserstar was the only ship close enought to respond in a timely manner that it wouldn't because...?
I don't understand the difference between flexibility of humans on a Laserstar and those on a smaller gunship. Robots are defined by their mission, but humans can use resources at hand, even if they aren't optimal for the purpose needed. That's what I meant by flexibility, not merely DC functions. Please don't try to artifically limit people; whether you meant to or not, that was the impression you gave.

Ferrell

Byron said...

The humans are only a few light-seconds away. They are definitely in the loop for what you propose. I suppose you have a point as it was written, but I assumed that the nearby humans bit would be obvious.

Anonymous said...

Rick, your blockading constillation still needs humans on-site to deal with situations that need more than 40+ minutes to resolve: take the example of an inbound spacecraft that suddenly changes course; is this an attack, an undeclared emergency, or perhaps a hijacking; you may only have a minute or two to decide whether to shoot ot not. A human commander on the spot could make this decission in a much more timely manner than someone back on Earth (or even Mars).

Ferrell

Byron said...

What do you mean? I'm really confused now. Rick proposed having a tender at Mars. That's only maybe 30 seconds delay. And what do you mean, suddenly changes course? You do remember that this is plausible midfuture. That sort of thing isn't going to happen suddenly. The acclerations are far too low.

Milo said...

Tony:

"I don't see how deep space warfare can erupt in an environment where interplanetary propulsion systems are very low thrust. No matter how efficient such drives would be, interplanetary travel would be seasonal and relatively slow."

So the war takes a while. An invasion that's delayed by one month would give the enemy some time to prepare, but could still work if you have a strong armada.

The enemy could use this time to crank up their planetary defenses, or to mount a deep-space intercept mission.

Of course, if Mimas and Rhea start fighting each other and Mars's government doesn't already have forces in orbit around Saturn, then it may well be that Mimas and Rhea will finish their dispute on their own by the time an intervention from Mars will arrive, which severely limits the value of attempting one. (But there's still some merit to a punitive expedition after the fact.) But if Mars simply wants to conquer Rhea, and Mimas has nothing to do with it...



Byron:

"I still don't get why everyone's fixing on AI. You don't need it for RDs."

You do. If orders from home take minutes to arrive, then the AI needs to improvise what to do between orders. While "go over there and shoot at anything you see" is an order that can reasonably be given by remote control, individual shot aiming (for example) will need to be calculated locally.



Rick:

"I have used the term 'orbital space' frequently, but it is a bit slippery."

The Hill sphere is a useful scientifically-grounded definition for a planet's "zone of control".

This may not be exactly the definition most convenient for military use, but it'll do.


"But for strategic purposes, you can be well beyond orbital space and still be in local space."

Politicaly speaking, "local space" is going to come down to weapon ranges. Sovereignity extends to the tip of your sword.

However, you need to get captured by a planet's gravity in order to reliably stay near it.

Byron said...

Milo:
You do. If orders from home take minutes to arrive, then the AI needs to improvise what to do between orders. While "go over there and shoot at anything you see" is an order that can reasonably be given by remote control, individual shot aiming (for example) will need to be calculated locally.

That doesn't require AI. I'm speaking of RDs, which I defined as pretty much being captained by humans. That is to say, minimal light lag, and no need for anything more than rule-based logic.

Anonymous said...

Byron: "2. Societies want their warriors to come home from war. Drones reduce the human cost. I know that many of you think this is objectionable, but people will always attempt to minimize their casualties."
Outside of all-out war, this might be an advantage for manned warships, not a disadvantage (depending on the political situation).
If your crewed ship has no weapons (as you stated earlier), I can destroy all your drones and therefore your offensive capability without killing anyone.
There are situations in which you might want to force an ennemy to escalate the conflict or back down... or in which you might simply want to bluff. That is best accomplished with a manned ship carrying powerful weapons which can't be easily disabled without killing the crew.

-Horselover Fat

Byron said...

Horselover Fat:
That makes a good bit of sense. Though I do question the idea of a limited space war. The idea of a limted war usually involves one side being able to hide. That doesn't work in space.
Even then, the mission you describe seems better suited to a patrol vessel then the battlefleet, which is what I was dealing with.

Anonymous said...

A war in which victory is impossible or too costly is necessarily limited. That's why WMDs have tended to limit the scope of wars.

A big ship has a larger crew than a small ship (so its loss would be less acceptable) and is a more credible threat with more interdicting power and so on. So it might well make a much better card to play in some situations.
Political leaders have been known to put whole fleets in harm's way to get the political outcome they wanted.

My perspective is that large battle fleets are unlikely in the plausible midfuture anyway.
The cost/benefit of allowing conflicts to esacalate that much stinks outrageously and the strategic situation is unlikely to warrant a peacetime "naval" arms race as happened on Earth in the lead up to WWI for instance.

-Horselover Fat

Thucydides said...

Laserstars will be huge mostly because they can. Once you have a honking reactor or three, powerful engine, tankage of fuel and remass, giant booms for the liquid droplet radiators and enclosure for the 5+ metre mirror, having a 500 metre long liniac seems almost an afterthought. Given a kilometre long liniac allows the FEL to access energies up to X ray range, there is no reason NOT to go this route. A ravening beam of death that can cut through metals at ranges measured in light seconds or set you on fire a light minute out is something to be well and truly feared.

A centrifuge 40 metres in diameter is sufficient for the crew to live in comfort without inducing excessive spin or odd torques to the ship, compared to the 500 metre long truss housing the Xaser, it can easily fit along with KKV busses, targeting drones or other assorted stuff. A KKV bus designed to overwhelm an enemy laser will be quite large anyway, so robust cradles built in along the truss will be capable of addressing this issue.

Damage control will probably be moot, a laserstar can deliver huge amounts of punishment (literally cutting the enemy ship into pieces for a ravening beam of death) while earlier discussion about KKV's indicates that once the point defense is overwhelmed, the damage is catastrophic and the vehicle/installation will be pounded into rubble.

Assumptions about human culture are dangerous as well; we care a great deal about getting our people back, but there are current examples where humans sacrifice themselves to accomplish the mission (Japanese kamikaze pilots in WWII, "Black Tiger" LTTE suicide bombers in the 1980-1990's and Jihadis today). Ancient Greeks also believed that the persuit of glory overrode the preservation of life.

Tideflat said...

Assumptions about human culture are dangerous as well; we care a great deal about getting our people back, but there are current examples where humans sacrifice themselves to accomplish the mission (Japanese kamikaze pilots in WWII, "Black Tiger" LTTE suicide bombers in the 1980-1990's and Jihadis today). Ancient Greeks also believed that the persuit of glory overrode the preservation of life.
That is a good point, but most of those groups were people fighting in asymmetrical warfare (on the smaller side). So those groups (in exclusion of the Japanese) would probably not have the resources to field a warship.

Citizen Joe said...

Woohoo! Kilometer long xray FEL stars! Ya, I think I brought up the five mile long design way back when... The trick is that you're dealing with minutes of light speed lag. Yes, you should be able to annihilate someone from well out of their range, but only if they aren't maneuvering. So the tactic there is to use your manned ships to coax the enemy vessels into entering the cone of death at just the right time.

On the cost justification side of the equation, the light minute range damaging Xray laser could also be tuned to microwaves which makes your Xaserstar also your communications hub for the entire system.

Luke said...

Tony:

Since we seem to be taking as many cues as possible from Atomic Rockets, it might serve everyone well to review the space war weapons page that deals with lasers. It turns out they probably aren't very long ranged weapons. That means the dominant weapon system is still going to be the guided missile.

Lasers can be long ranged weapons depending on your tech assumptions. An uber-realistic ultra-near future laser weapon might be a 1 MW laser emitting at 1 micron wavelength and focused through a 2.5 meter diameter mirror (so you can fit the mirror in a launch vehicle in one piece - I'll ignore segmented mirrors like the James Webb for now). This can start to damage steel with a 1.25 meter spot size, which means a range of around 3,000 km. This is perfectly adequate for engagements in near Earth orbit, although dwell times might be rather long in some cases (I am also ignoring effects to components other than steel - heating seals and lubricants and sensors and electronics to failure, for example).

At the other extreme, a 1 GW laser emitting 0.01 nm hard x-rays focused by a 25 meter zone plate could cause the same sort of damage at a distance of 10000 light seconds, or about 3 light hours.

The real question of the utility of a laser is not its range compared to a kinetic, but how many incoming kinetics can the laser shoot down before impact compared to how many kinetics can be launched by the enemy. If the laser can shoot down more kinetics than the enemy can launch, the laser can move in close and put the heat on the other guy. If not, then bye bye laser. Again, whether this happens depends on your tech assumptions.

Luke said...

Bryon:

You're also ignoring the economic side of war - war is expensive, AI may be expensive. People have been, currently are, and probably always will be, cheap.

People may be cheap, but people in space currently are, and probably always will be, expensive.

Luke said...

Raymond:

I don't quite buy the "hard limit" on propulsion units, powerplants, sensors, etc. I don't see any technical or industrial reason why smaller and cheaper powerplants couldn't be produced in greater numbers, especially by an economy on a war footing.

There may be hard technological or physical limits. Nuclear reactors, for example, do not scale down well. At the very least, you need at least a critical mass of fissile fuel.

Kinetic buses have very different propulsion requirements than laserstars would - the former benefits from quick acceleration and high closing speed, the latter benefits from long range and low closing speed. Not to say both wouldn't have elements of the other's weapon systems, but the nature of the primary weapon is a major factor in propulsion unit design.

I would think that the kinetic buses could use the same sort of low thrust, high delta-V thrusters as laserstars. They use these to put them on a high speed intercept course with the target. Then when they get close, they release the kinetic warheads with high thrust low delta-V rockets.

Luke said...

Tony:

Only if it can be held on target long enough -- or even hit it at all. That's highly questionable.

At ranges where light-lag is not an issue, it is not highly questionable with modern technology. The tech to hold a telescope (the thing you use to direct the laser beam) on a diffraction-limited bearing is well developed today, with technologies such as active vibration control, adaptive optics, and all those other goodies.

Not hitting, or failure to hold the beam on target, only becomes an issue when the target can change its position by more than its linear dimensions within less time than twice the light speed delay. At intermediate ranges where evasion such as this is possible, it also tends to require large expenditures of propellant. At these ranges, lasers do not need to hit their target to be effective, if they can force it to use up so much propellant that it can no longer complete its mission.

No stealth in space is a statement of theoretical principle, not practical application. It implies that if you could look everywhere at once with powerful enough instruments, you wouldn't miss a thing. But you can't look everywhere else, and your instruments will not be as powerful as possible. So you will have to distribute your instrumentation and focus on bodies of interest. Putting decisionmaking capabilities close to many -- or even all -- of the instruments throughout the distribution only makes sense.

But you can get sufficiently close to looking everywhere that no one on an interplanetary orbit can hide. To quote from a post I recently made on another forum

The Large Synoptic Survey Telescope needs to collect about 500 photons
in order to get a signal about 5 times the fluctuations in the noise.
In space we could do better because we will not be fighting
atmospheric scattering (the major source of noise in LSST), but let's
assume we need 500 photons for a detection using a mercury cadmium
telluride infrared detector with a detection band from 0.8 micron to
25 micron wavelength. MCT gets a quantum efficiency of about 0.75
(that's 75%) over a fairly broad spectral range. We set our
collection area at one square meter and our exposure time at one
minute.

Our target will be a 1 kW gray-body source radiating at 300 K. The 1
kW could be from reactor waste heat, hot rocket bells, or sunlight-
warmed surfaces. The target will be emitting 5.5e22 photons per
second. We thus need our detector to occlude a solid angle of 2.6e-21
sr for a 500 photon signal in one minute. This will occur at a
distance of 2e10 m, or a bit over a light minute, or 0.13 AU.

The scaling laws should be fairly obvious for everything except
radiating temperature - going to a 1 MW source, for example, gives a
detection distance of a bit over 4 AU. If you go up to LSST's 35
square meter mirror you can detect the 1 kW source at about 0.8 AU
with a 1 minute exposure. For temperature you pretty much have to re-
integrate the Plank spectrum over your detection bandwidth.

The LSST images a solid angle of about 0.003 sr, so a similar mirror
design needs about 4300 exposures to do a full sky scan. At one
minute each this would take about 3 days.

You can play with the numbers to optimize your detection scheme
against various threats (actively thrusting spacecraft, passively
drifting spacecraft, and so on), but the basic conclusion I keep
coming to is that long range detection on the order of AU distances is
pretty much inevitable for a space-going civilization.

Luke said...

Tony:

And in self- defense, the more energeticthe laser, the longer cycle time it is likely to have, which means it can't target, even at short range, all of the brilliant pebbles coming to kill it.

The closest things we have to modern laser weapons can fire continuously - no cycle time. This is both for high power solid state lasers being developed as weapons and free electron lasers being developed as weapons (although to be fair, free electron lasers have a beam structure - picosecond or femptosecond light pulses emitted in bursts lasting microseconds, with milliseconds between bursts. For practical purposes, however, this is continuous).

So mow it makes sense to install several defensive lasers and/or particle beams.

Not that I can see. A single laser system (which might be made up of several chained laser units that can combine their beams into a single coherent beam) can be stuck in the middle of the spacecraft and direct its beam out through several beam pipes to any of several beam pointer telescopes - these may be small agile beam pointers for close in point defense, or great big mirrors for long range zapping. Particle beams are similar, except that now you use magnets rather than mirrors to direct the beam.

Thucydides said...

Not that I can see. A single laser system (which might be made up of several chained laser units that can combine their beams into a single coherent beam) can be stuck in the middle of the spacecraft and direct its beam out through several beam pipes to any of several beam pointer telescopes - these may be small agile beam pointers for close in point defense, or great big mirrors for long range zapping.

So now we have the design of the laser star.

The core is the Liniac, surrounded by triangular radiators (which serve several secondary duties). The spaces between the radiators is used as the carrying cradles for KV busses, a control ship or other secondary craft. The triangular radiators face in the opposite direction of the engine bell (i.e. they taper towards the rear of the ship). The front of the ship holds the huge primary mirror (or diffraction grating if an Xaser), but light pipes run up the front face of each radiator ending in a secondary mirror for point defense. The other reason for triangular radiators is to stiffen the central structure so the optical trains will be aligned and vibration free.

Anyone good with sketch up?

Byron said...

Horselover:
For that situation, I'd use a hab module attached to one of my laserstars.

Luke:
Thanks for dropping in.
As to "Bryon" I think you mean Bryan, as I know I didn't say that.

As to the hard limit, I don't see that being a huge issue. Unless you're trying for really tiny ships, you should be able to build the required reactor. I've heard the reactor on NR-1 was about the size of a desk.

jollyreaper said...

Been reading over the spherical cow pages with kineticstars vs. laserstars. Interesting stuff! And it seems less clear which is the ideal solution.

I would tend to agree with the assertion that laserstars represent the best flag-showing vessel and would, by virtue of the ravening beam of death be immune to weaker attacks.

The primary advantage of the kineticstars is that the manned portion never needs come within range of the enemy for attack -- either the kineticstar itself is the ferry for the kinetic kill buses (carrying them FTL for deployment in a system) or the buses themselves are FTL-capable and operate entirely in an autonomous fashion.

jollyreaper said...

It seems like, in practice, the kinetic weapons would represent "grid killers." The multiple launch rocket system MLRS used by the US Army is called such. Depending on the loadout, the rockets could be carrying hundreds of submunitions. You target a battery on a grid coordinate and fire, you know pretty much everything in it is going to be dead. Great when talking about formations in the open desert, less useful when talking about insurgents in a town you're trying not to blow up.

If the kineticstars need a long prep time for building up to speed for attack, that could also be a constraint in their employment.


So if you're mounting a heavy assault on a defended planet, lead with kineticstars and follow up with laserstars. You can still keep your manned laserstars 30 lightseconds back and safe from engagement while passing orders to the foremost unmanned laserstars.

jollyreaper said...

So when does it make sense to pit laserstar vs. laserstar as opposed to kinetic vs. laserstar? Not sure. But you could possibly see a parallel towards hypothetical pre-WWII discussions of the merits of attacking a battleship with cheap planes versus an expensive battleship. The plane advocates would say planes are cheaper in terms of materiel and lives than a battleship and planes can also engage more quickly than a battleship could. The battleship proponent would scoff about the effectiveness of the aircraft and say that they might work against lighter targets but a battleship could only be defeated by another battleship. Early in the war, this was not true. Planes could mutilate any number of surface combatants. The introduction of increased volume of AA fire, proximity shells, and radar made Japanese attacks against US task forces suicide runs even before kamikaze tactics were adopted. So for two equivalent tech formations staring each other down in 1945, then air attacks might be suicide and the only practical way to crack the enemy fleet would be a surface action, guns and torps versus guns and torps.

Relative flexibility of kineticstars vs. laserstars would also depend on whether FTL only works between stars and everyone is on reaction engines in-system or whether you can FTL everywhere. In-system FTL means kineticstars can be jumped the moment they show up. But if inertia is maintained, a kineticstar could make the run up to attack speed outside of the system, FTL in to proper attack range and dump the weapons at that point.

To keep the right flavor, we might want to stick with the niven/pournelle drive, FTL only works at the edge of the solar system and you're on reaction engines inside the primary's gravity well.

jollyreaper said...

Byron:

Jollyreaper:
I still don't get why everyone's fixing on AI. You don't need it for RDs. Period.


Depends on how "remote" your remotes are.

I dislike the word "drone" because it carries a lot of connotations that would probably be less accurate in the future.

Like with the air-to-air missile discussion, any pilot living in the Vietnam-era would roll his eyes and say "Yeah, sell me another pipe dream." They were terrible. Any pilot in the modern era would say "Yeah, I wouldn't want to fly without a gun for backup but I doubt I'll ever use it; missiles are scary-effective."

That being said, any drone is going to be working at a certain level of abstraction -- you tell it to shoot a target and its going to have to handle the rest. If we look at a current example with the USS Vincennes incident, the crew mistakenly flagged the airliner as an F-14. Now all the rest of the engagement went by automatics after the button was pressed -- radars tracked, missiles flew, civilians died.

Will a computer system make less mistakes? That's the big question. We know humans are bad enough at this sort of thing, witness the history of blue-on-blue kills and all matter of "collateral damage."

At any rate, unless your remotes are directly slaved to the command ship's systems and are a light-second or two away, they're effectively on their own. And really, the AI part comes down to "pressing the button." On the manned ship, everything after the button is pressed is automatic; the gun isn't manually loaded, manually trained, manually fired. Nor would it be on the unmanned ship -- the difference is that after the CO issues the "weapons free" command, the computer gets to decide who to shoot at.

jollyreaper said...

Most people are going to be very scared of the ED-209 scenario, software bugs making a computer less reliable than a scared 18-yr old recruit with a gun.

See this story below: robot cannon kills 9, wounds 14.
http://www.wired.com/dangerroom/2007/10/robot-cannon-ki/

Now if we think about this dispassionately, is a malfunction due to poor programming or poor maintenance in an elevator any different from a robotic weapons system? For example, there's the classic software bug in an X-ray machine that gave people a ridiculously high dosing and led to deaths. Is that really any different an error from a sentry gun shooting the wrong person? No, but most people would still be more terrified by a robotic sentry dog hunting them down and killing them than by a Toyota's computer sticking and putting them into an uncontrolled acceleration. Both are software flaws but one leads to death by car accident and the other is death by robotic attack dog.


I don't like the rider command ship idea for a number of reasons:
1. It would have to have a specialize carrier. That strikes me as unlikely. The alternative is going to hinder fleet performance as everyone else has to go slow.


Depends on whether you do 20g torch drive burns or if we're sticking with milli-G performance.

2. Any rider will have to be small in comparison, particularly under 1. That doesn't match what I see. The command ship will likely be the same size as the standard laserstar, but loaded with defenses and crew instead of laser.


That's certainly one way or doing it. I think you could easily see both attempts made in the same universe. It would be a matter of doctrinal preference from one navy to another. The advantage of the detachable manned vehicle is that it gives you a ready-made escape craft if the fleet's in trouble. (with the question of whether the setting's technology makes a super-fast fleeing vehicle that can outrun enemy attack plausible.)


3. It suffers from the fact that it can't run independently. Being able to sacrifice drones is one of the best things about them.


My thought with the manned component would be that if you have a task force of 100 laserstars entering a system and the admiral decides to split off 10 to go look at the other side of the system, he would order a detachment commander to take his ship and attach it to one of the 10. Now you have manned control of the detachment. If the manned laserstar is badly shot up, the humans could then move their ship to an undamaged laserstar just like an admiral shifting his flag.

Rick said...

You all are covering so much of the ground that there isn't a whole lot for me to add!

But let me emphasize again the enormous scale of space. For example, Earth's L1 and L2 points, at the inner and outer edges of its Hill sphere, are about 1.5 million km away, roughly 4x lunar distance. These L points would be good positions for a blockade force (etc) - they are not stable, but the delta v needed to keep position is minimal.

Set aside milligee drives for a moment, and consider a drive capable of covering those 1.5 million km at a steady 1 g. It will take 5 hours to cover the distance, and mission delta v is about 173 km/s.

This is torch level performance, basically operatic. But it still takes 5 hours to close the range, and the trajectory is a pretty damn unmistakable attack profile. For more Realistic [TM] drives the time scale will be longer.

So whatever force you have there is not really going to be facing snap rules of engagement decisions that have to be made in seconds or even an hour. That means the human in the loop could potentially be in Saturn space.

Mind you, I wouldn't recommend this, but as a thought experiment, just how close to the action of a space battle does the human in the loop need to be? The key human-level decisions seem to have a remarkably long time scale.

Luke said...

Bryon:

As to "Bryon" I think you mean Bryan, as I know I didn't say that.

You are right. My apologies. I can only blame clumsy fingers or brain-hand disconnect, because I was looking right at Bryan's name as I typed it.

As to the hard limit, I don't see that being a huge issue. Unless you're trying for really tiny ships, you should be able to build the required reactor. I've heard the reactor on NR-1 was about the size of a desk.

Many of our current spacecraft are already only about the size of a desk. There's also the issue that shielding of a reactor goes as its area while its power output goes as its volume, which tends to favor larger reactors, particularly for manned missions. Of course, cooling also scales as area (of the radiators).

Still, the scaling limits of even small reactors can become important when looking at kinetics. If your kinetic impactors are meter-long, centimeter-wide tungsten rods, you don't want to attach a desk-sized reactor to each of these. This naturally leads to missile buses with reactors and individual kinetics with chemfuel rockets. If your reactors do scale down so that they can be installed directly on your kinetics, then you can get rid of the bus (ignoring other factors like delta-V versus thrust tradeoffs, cost, and so on. Let's say that good scaling properties are a necessary but not sufficient condition to eliminate the bus).

And then when you get to fusion reactors, the scaling issues get even worse (as far as we can tell, anyway - if ITER or NIF is the smallest that you can make a fusion reactor work, you will only have fusion on large spacecraft. If some of the more speculative fusion methods work, you might be back to bus-sized reactors again).

jollyreaper said...


Mind you, I wouldn't recommend this, but as a thought experiment, just how close to the action of a space battle does the human in the loop need to be? The key human-level decisions seem to have a remarkably long time scale.


That all depends on how smart your expert systems are. Skeptics will point to Deep Blue and Watson and say "A computer did not beat the best human; teams of really smart humans made a machine that could beat a smart human." If I use a club to beat up a bare-knuckles boxing champ, it would be inaccurate to credit the club for the act.

So if the argument goes that an expert system can be no smarter than it is programmed for, then a good definition for strong AI would be a system that exceeds its programming through learning.

"How much can go wrong when you're not looking?" The same can hold true for AI's or soldiers and sailors. Left to their own devices, the sailors will yarn the logs, shirk their duties and break into the rum locker. AI's might not loaf about but could they recognize and adapt to new weapons and tactics from the enemy? For your classic scifi strong AI -- superturing and superhuman -- you can leave it in charge and not have to check back in.

There's probably a good story in there about humans who leave a superturing in charge of something like that and don't anticipate how creatively it might interpret its orders. Say "enforce an orbital blockade against this planet because they've been naughty and warlike." If the instructions were worked as "until they are no longer naughty and warlike," the assumption by the human masters might be "until they become peaceful on their own" and the superturing might see it as "I'm supposed to have a hand in civilizing them."

I'm sure that story's already been written, though!

Byron said...

jollyreaper:
Depends on how "remote" your remotes are.
Red herring. I explicitly mentioned RDs. If you look up above, these are defined as ships that are basically given remote orders by a human crew. On any spaceship we've proposed, that crew is only going to be a couple of people. The automation needed for that sort of drone is well within modern technology. All you need is some basic rule-based logic. Things like deciding to shoot, and what at, are made by the humans.
I will not respond to any more of these type of comments. My statement about not needing AI was explicitly meant to apply to ships of the sort I just described. No more.

Nor would it be on the unmanned ship -- the difference is that after the CO issues the "weapons free" command, the computer gets to decide who to shoot at.
That is not what I've been proposing. The CO tells it what to shoot at. The only weapons under automatic control would be allowed to fire at anything on a CBDR course, and only those things, and only in combat.

Depends on whether you do 20g torch drive burns or if we're sticking with milli-G performance.
Um, the torch drives have never really been a subject for discussion. The entire debate has been under plausible midfuture assumptions. And that still doesn't solve the problems raised. The rider would alter mass and mass ratio, hindering carrier performance. Every other ship would have to match that performance. A specialized carrier avoids that, as it's designed to carry the rider and still make fleet standard.

As to shifting command, I'd just send a command ship. It's a lot more likely to survive a battle.

Luke:
Don't worry about it. I get called Bryan or some variant therof all the time. But you did it again.
I haven't been looking at miniature drones. I do know that you can't make practical desk-sized combat drones, but a desk-sized NERVA or nuke-electric reactor might power a ship of only a couple hundred tons loaded, which is smaller than most manned ships under consideration. Actually, I see my drones as manned ships without the men.

Milo said...

Jollyreaper:

"If I use a club to beat up a bare-knuckles boxing champ, it would be inaccurate to credit the club for the act."

It would also, however, be inaccurate to claim that clubs are ineffective.


"So if the argument goes that an expert system can be no smarter than it is programmed for, then a good definition for strong AI would be a system that exceeds its programming through learning."

But it was programmed to learn!

Anonymous said...

Byron, sorry about not getting back to you sooner; day-job.
Anyway, a low-thrust-high-ISP transport that was previously expected reaches Mars space but then lights off some chemfuel rocket boosters and radically alters trajectory. At that point, someone has to decide what is going on and what to do about it. If the human commander is light minutes away (Earth) or light seconds away (Mars), instead of 'merely' being a few tens of thousands of kilometers away, whatever the ship is doing may well be done by the time either of the faraway commanders can react. People, being people, do weird, unexpected things all the time and most people would want another person to counter it, not an AI.

Ferrell

Thucydides said...

Ferrell

IF a ship suddenly lights off a chemfuel booster or NERVA NTR for a high thrust burn close to my warship I will assume hostile intent. The closest analogy in the here and now is a car approaching at high speed and ignoring non lethal warnings directed against it (flashing lights, pen flares, hand signals etc). Police or soldiers would have to assume hostile intent and escalate to lethal force. In 22nd century space, this sort of manouevre would fit the ruleset for weapons free and unleashing a ravening beam of death.

Byron

The smallest nuclear reactor that I have ever heard of was described as a series of channels microns wide which directed individual atoms of D2 ,http://www.foresight.org/Conferences/MNT05/Abstracts/Donoabst.html Should this prove practical, powerful reactors the size of laptops could hold hundreds or thousands of these devices in parallel, and shrining practical devices down to "garbage cans of death" size.

Militarized space will be considered if and when groups of people have the potential to drop rocks on the Earth. Taking control of every site where space miners reinserts the people element into space combat, which is something missing in a lot of this discussion

Citizen Joe said...

Re: AIs

Children are also created things. Do the parents get credit for the works of the child? What about the teachers in school?

The answer is 'sort of'... Teachers get paid in advance for their skills. Apprentices usually work for free for many years, with credit going to the master. Parents have their social security paid by taxes on their children's wages.

I see no reason why AI's should be any different in complexity of compensation.

Anonymous said...

Thucydides said:"IF a ship suddenly lights off a chemfuel booster or NERVA NTR for a high thrust burn close to my warship I will assume hostile intent. The closest analogy in the here and now is a car approaching at high speed and ignoring non lethal warnings directed against it (flashing lights, pen flares, hand signals etc). Police or soldiers would have to assume hostile intent and escalate to lethal force. In 22nd century space, this sort of manouevre would fit the ruleset for weapons free and unleashing a ravening beam of death."

Ah, but that would be the response of a robot. You have to ask some questions (in a matter of seconds)
A. is the ship aimed at one of my ships?
B. Is the ship going to impact Mars?
C. is the ship manned? and if so, is there anyone on it except crew?
D. If I destroy it and it turns out it was a political kidknapping, will I be exicuted after a public trial?
E. Can I intercept the ship and put a commando squad on it?

I'm sure there are other questions, but if you only have a few seconds, you need to answer the most important ones. Yes, 9 times out of ten, blowing it into flenders would be the correct option, but it isn't the only one. A robot doesn't have any concept of "don't shoot the hostiges" :0 So having an on-site command crew might be a good idea...better to have it and not need it than to not have it and need it later...

Ferrell

Citizen Joe said...

Except that crew would probably have the same rules which would dictate the same effect.

Byron said...

Ferrell:
Again, time scale of space. At 1 G, it will take close to 10 minutes to come to a stop from a mars trajectory. A few seconds light lag isn't going to matter that much.
As to robots, humans can't always be counted on to make the right decisions. We would be better than a computer, but a human isn't perfect, either.
I expect that there will be a large body of international law governing these sorts of missions. The robots will be programmed in accordance with this law. For example, take a ship of any kind parked in someone else's orbit. What constitutes a kinetic threat that allows it to shoot?
1. An object is on a CBDR course.
2. The ship has attempted to avoid it and it has tracked the ship, or there are enough objects so that it is impossible to dodge.
3. The ship has hailed the object, and instructed it to change course, and it has not complied.
If all 3 are fulfilled, then everyone recognizes that the ship can shoot, no matter what the incoming object is.

As to the specific example, a ship that attempts to avoid a legitimate blockade may be fired upon. It's a lot harder to have the "car not stopping at a roadblock" scenarios in space, as everyone should be duly licensed and can see everything.

Thucydides said...

Even the more improbable scenarios could be programed into a decision tree; any AI will have the ability to screen thousands of sensor inputs and run the decision tree far faster and more comprehensively than any human or human crew (even if they all have ninja training).

As pointed out, even with a human crew on board ship (or human soldiers manning a Vehicle Check Point), you will end up with essentially the same outcomes. The Humans may come off worse simply because they will have bottlenecks and react more slowly than an AI; end result flaming wreakage on the human side.

WRT International law, the training, Rules of Engagement and circumstances of the incident should be the factors examined by the court; if the shooter had an honest belief that the oncoming object was hostile according to all available information and the ROEs were applied, then either human or AI crew will be OK. (This assumes the ICC is not hijacked by groups with ulterior ideologies or motives...)

Anonymous said...

After reading this entertaining thread I have a few thoughts ...

If you assume Remote Drones are possible, then the Minimum Crew Size of a "manned" ship: Will always be 1.

Since by definition you just moved the decision maker onto the formerly "remote" drone.

------
Whether or not AI Drones or partially remote drones makes sense really depends on your tolerance for mistakes. If you do not care that your invading fleet burns down all the civilian ships and combatant ships on the other side with impunity-- then you certainly dont need any Human crews on your attack ships.

Beyond that target selection will be the main criteria. And that will always be best with a human crew, Second best with a remote drone that makes no targeting decisions, and progressively worse depending on how much you are willing to let a AI ship decide to kill humans and other AI ships.

---
The repair idea was postulated - but redunancy in many cases will be more mass efficient, especially for combat mission times of months.

----
Orbital fights -- why assume that there will be no Ground to Orbit defenses?

A properly scaled ground based Laser would kick the robotic behind out of any Laserstar in a straight up fight -- it can be much more powerful due to heat management and power considerations.

Globally spaced submarines would be pretty amazing against an orbital attack, Nuclear reactors, Water as a heat sink, Stealth ... price.

Trucks and Aircraft would also be effective.

Any ground defender could see the space Laserstar better than the Spacecraft could see the defender.

Elukka said...

I think an important question when pondering automated vs. manned ships is if we can make them automated at all.

Why do we put five thousand people on aircraft carriers? Surely it would be immensely useful not to have to train and supply them, not to mention not having to design the ship for continuous habitation of thousands of humans.

In the Exciting Space Future, automation will no doubt have taken leaps forward, but will it be that good? What if the spacecraft is orders of magnitude more complex than a modern aircraft carrier? It seems like a realistic scenario to me that automation just isn't good enough to eliminate the need for crew entirely.

Anonymous said...

Byron, Thucydides, et al: owhere did I state in my original comment that the ship was 'oncoming', you just assumed it. So your solution to a potinially hijacked spacecraft is to destroy it. And if it is a manned or passenger ship, kill the hostiges...that doesn't sound like a PR friendly solution :) And, how easy would it be to 'trick' a robot warship to blow-up a shipfull of hijacked civilians?
If the ship is aimed at one of your ships, then shoot it; if it is pointed at Mars, then shoot it; if it is on an escape trajectory/slingshot then (if you can) intercept it and put a commando squad on board...but this last would mean that you had humans on board your blockade ships anyway; besides, wouldn't any blockade involve boarding and inspecting ships for contraband? So unless you have robo-troopers, you're going to have to have humans in your blockade constellation.

Rick; if your EU blockade constellation is interdicting the entire planet of Mars, then you either need C&C to be on Earth, or embarked in one or more command ships; if the EU contellation is only blockading rebal colonies, the add a C&C on Mars to the mix. However, if you need to board and inspect ships then you still need humans onboard...so you still need humans 'on-site' and having the command crew somewhere else makes less sense. It comes down to whether the intent is to kill any support from off-world, or if it is to cutoff support from Earth for the rebals. So, a fleet of indiscreminant killer robot warships, or a more traditional trade interdiction mission; the choice is yours...

Ferrell

Rick said...

Welcome to a new commenter! I do ask 'anonymous' commenters to sign a name or handle, so we have someone to respond to.

A couple of important provisos to my discussion. The needle is set more toward 'remote' than 'autonomous' because I'm concerned with battles between main force constellations well out in deep space.

Most likely the battle is for control of some planet's orbital space, but the defender has presumably chosen to fight well away from vulnerable civil population and infrastructure.

This is a restrictive set of conditions that happens to exceptionally favor remote/automated systems. But these conditions also happen - so far as I can see - to fit the top of the space warfare food chain.

Especially in operatic interstellar-empire settings, so long as deep space journeys are needed to get from planet to planet. If you can win constellation battles in deep space, you can defeat any attack against your worlds, and can with impunity blockade and cut off any hostile worlds.

Given that advantage, everything else pretty much amounts to mopping up.

Byron said...

Message to everyone:
I have been claiming drones are the best option for deep-space fleet engagements. Nothing more.

Ferrell:
I grow tired of this. Your scenario is contrived to make it seem that humans are needed. However, it relies on a long string of coincidences. You need a blockade, a hijacking (innocents aboard a vessel trying to break the blockade), and a high-thrust booster on the hijacked ship. Two stretch the limits of plausibility. The third is ridiculous. Claiming that this justifies humans is like claiming that because warships sometimes run aground, we should install huge external tires on all of them to help get them off.
All of the above even assumes that the scenario is possible under the laws of physics and how blockades will be conducted, which it isn't (though I won't go into that unless you insist.)

Anonymous:
If you assume Remote Drones are possible, then the Minimum Crew Size of a "manned" ship: Will always be 1.

Since by definition you just moved the decision maker onto the formerly "remote" drone.

What is that supposed to mean?

We've covered surface defenses before. I don't think any of us are eager for a rematch.

Elukka:
You're correct that it may not be possible. However, I doubt that's the case. If it is, then I'm wrong. This has already been covered, so I'll leave it at that.

Mangaka2170 said...

It's occurred to me that a planetary blockade wouldn't require that many ships to pull off. At orbital velocities, it only takes a few minutes or so to complete a revolution around a planet at low orbit. Therefore, if you had a ship on a polar orbit and two others orbiting above the tropics of Cancer and Capricorn, you'd probably have most everything covered, and all you'd need are a few strategically placed probes to spot anything attempting to lift off or approach the planet.

Any other thoughts on this?

Byron said...

Not even that. You sit back at GEO-level or higher, and wait. Anything is going to take a while to get to you from the planet, and you instruct any incoming ships to rendezvous with you. You can see them a long way off, remember. If they don't comply, blow them up.
Actually, send a missile to meet them way out. It latches on, and if they try to run, it blows up. If they refuse to allow it to dock, it blows them up anyway.

Geoffrey S H said...

@anonymous:

Please go through the whole thread again, and also read:

http://www.rocketpunk-manifesto.com/2010/09/space-warfare-xii-surface-warfare.html

Its a long read, but the figures are very instructive.

"We've covered surface defenses before. I don't think any of us are eager for a rematch."

Agreed, x10. I and everyone else ain't keen to read a flame war, and you won't beat Byron on the numbers. Please leave it at that. I'm sorry to sound harsh, but knowing your facts and numbers is absolutely imperative here.

"Beyond that target selection will be the main criteria. And that will always be best with a human crew, Second best with a remote drone that makes no targeting decisions, and progressively worse depending on how much you are willing to let a AI ship decide to kill humans and other AI ships."

We aleady have computers that can "learn". Are you suggesting that computers cannot distinguish between civilian and military targets? I'm sorry if I'm missing something here, but even the most basic programming should be able to tell between different types of signatures, even if its a visual profile- or who is shooting at you.

Citizen Joe said...

Perhaps a layered approach? First wave would likely be the drones sent out to the deep space fight. That way the decision to commit actual troops can be decided based on the counter attack. If your drone attack force is destroyed, you can still withdraw without losing your main ships. If your defense drones get destroyed, then you KNOW that those blips are hostile. Then you have those weeks or months to prepare before the invaders arrive.

Milo said...

Rick:

"operatic interstellar-empire settings, so long as deep space journeys are needed to get from planet to planet."

Which deep space are we talking about? In those settings, you need to specify whether you're in interplanetary space or interstellar space. (Unless you're using wormhole/jump-based FTL, in which case you never actually travel through interstellar space.)

Since interstellar space would be crossed through warp drives/hyperspace/whatever which do not obey anything resembling Newtonian physics, it's anyone's guess what battles in that locale (if your FTL mechanism even allows them) will look like.



Mangaka2170:

"At orbital velocities, it only takes a few minutes or so to complete a revolution around a planet at low orbit."

You mean a couple hours, right?

Anyway, low orbit is a dangerous place to hold a blockade from, since it puts you in reach of surface-to-orbit defenses. A blockade would be waiting them out in high orbit, intercepting traffic from a safe vantage point. (Exactly how high an orbit depends on available weapon ranges.)


"Therefore, if you had a ship on a polar orbit"

Incidentally, while a polar orbit is a good vantage point relative to the ground (since you'll eventually pass over every part of the planet after a number of revolutions), it's no different from any other orbit with respect to stuff in space (which simply doesn't care about the planet's rotation).

jollyreaper said...

In relatively hard settings, the lift ability from planets would be pretty dismal. Industry is in space for a reason and the primary cargo going from ground to orbit qod likely just be people or luxury goods. Grain shipments and Other bulk commodities would require the kind of supertech drives that make you winder why the goods can't be synthesized from atomic feedstock.

But with slightly softer tech, there's the possibility of surging a warfleet from the surface. If planetary industry is underground, the first warning anyone in orbit would have would be the launch plumes.

Of course, there's also the question of just how far planetary lasers could be trusted to reach. There might not even be a need for that reserve fleet...

Rick said...

Remember again that my discussion is limited in scope to 'space combat' in a narrow but important sense - main force combat in deep space, and constrained by known laws of physics. (Which should deal with Milo's point!)

I don't dispute at all that many other important circumstances in a space war could involve more complex on-the-spot decision making, requiring either humans or AIs far more advanced than we know how to devise even conceptually.

But if largely robotic forces can fight the big pitched battles that determine who has broad freedom of movement versus who does not, that is a very big deal.

And if instead you want a classic pseudo-naval setting, with capital units having crews in the hundreds or thousands, you can't (IMHO) simply take it for granted, but have to justify it in the context of the settiing.

Not that the realism police are actually going to arrest you if you don't.

Thucydides said...

I will also take issue with Ferrell's interpretation.

While any ship is potentially a weapon due to the vast amounts of kinetic energy that could be released by a colision, neither the manned or unmanned piquets or laserstars are likely to take action unless there was something threatening about the ship in question (AKA Target). IF you say your exclusion zone includes a separation of "x" kilometers and a closing velocity of no more than "y" Km/s, then anything which breaches the inclusion zone is a target by definition according to your ROE's.

It won't matter if the Captain is Japanese or assembled and programmed in Japan, the conditions are set and woe betide any officer who ignores the ROE's.

The second objection is technical, any laserstar with a ravening beam of death is a precision instrument which could simply shear off a radiator panel or drive assembly (or cut through the main truss) from a considerable distance rather than kill everyone instantly. The primary mirror is also a great telescope, so the ship can observe the vessel, record and catalogue it long before the laserstar itself arrives in high orbit. Indeed. from several light hours out, the task force commander (wherever he is) will probably have drones taking a look and at least one laserstar with the mirror unshuttered to take a close look at system traffic, do pattern analysis and so on. If the enemy responds by starting an eyeball frying contest with the unshuttered laserstar, then its on...

Surface mounted lasers may well have more power, heat sinks etc., but will also have limited fields of view. Should the constellation commander know or suspect there are powerful ground mounted systems he can simply remain in the highest practical orbit to limit the defender's effectiveness (and we are talking potentially almost the distance of the Earth's Moon from the surface of the Earth). The only ASAT that has any practical application at that point would be an ORIOM powered torch capable of 100g acceleration and covering millions of kilometers in mere hours. I doubt that base would be very popular among the locals though.

Milo said...

Rick:

If you were constrained by known laws of physics, then you wouldn't have an operatic interstellar-empire setting.



Thucydides:

"IF you say your exclusion zone includes a separation of "x" kilometers and a closing velocity of no more than "y" Km/s, then anything which breaches the inclusion zone is a target by definition according to your ROE's."

What about a ship that's entering the exclusion zone while loudly broadcasting an "aaaah, our engines are broken, help!" message?


"Indeed. from several light hours out,"

Several lighthours out? Eris's orbital radius is only 9.5 lighthours out. Jupiter is less than one lighthour.

A span of several lighthours basically covers the entire solar system.


"Should the constellation commander know or suspect there are powerful ground mounted systems he can simply remain in the highest practical orbit to limit the defender's effectiveness (and we are talking potentially almost the distance of the Earth's Moon from the surface of the Earth)."

Actually, a higher orbit makes you more easy to see over the horizon, not less. To take advantage of enemies' "limited field of view" you have to fly low to the ground.

Also, the surface-to-orbit defenses don't need to be immobile bunkers, they could be mounted in vehicles like submarines or scramjets.


"The only ASAT that has any practical application at that point would be an ORION powered torch capable of 100g acceleration and covering millions of kilometers in mere hours."

You're launching from the ground. If you have field of view problems, you can use an airbreathing cruise missile to cover most of the distance.

The US is already looking at developing "Prompt Global Strike" technology that can hit anywhere within an hour.

francisdrake said...

The CIC
I guess the main reason to justify the presence of a human crew in a space battle (aside from Burnside zeroth's law) is decison-making, like the officers in the combat-information-center of a modern warship or in a bunker:

Information from various sensors is displayed on screens in a very stylized, iconized form. The information is interpreted and possible options are evaluated,
using a lot predefined algorythms. Decisions are made by the commanding officer and forwarded to the robots out there.

Normally these commanding duties would be performed by well protected staff, far away from the front line. But lightspeed-lag requires them to be uncomfortably close to the business.

I agree with Native Jovian, if you need a crew present in your spacefleet, it is probably best to have them in a combat-capable ship. Although the combat cabability may be focused on self-defense (the king of a chess game comes to my mind ...)

The Battle of New Orleans
On the other hand, you may avoid the decison cycle alltogether. Take the decision first, then send your robots on a clear and simple mission.
While this deprives the commander from making adaptive last minute decisions, it removes the human crew from the battlefield.

Not-so-ancient warfare on Earth gives examples, like the battle of New Orleans in 1812, two weeks after peace had been declared. The news had not yet travelled to the troops, so they fought according to their previously received orders.
That would a story background for a not-so-bright ending, showing off the absurdness of war.

The reason behind
Step back and think of why space war is waged at all:

Denial - Deprive somebody of something.
Prohibiting the enemy from doing things in a way he would like to do.
This includes restricting his movements and destroying his assets

Conquer - Put troops on enemy ground
The manned spacecrafts would rather be (armed?) troop transports,
which could very well can be converted commercial liners.
They are high-value targets as well, so they would rather come well after the unmanned fleet up front has beaten the enemies defences into rubble.
But what if your robotic fleet has failed? What if the enemy prevails? Then you are closing in on the enemy, with lightly armed transports, with too little delta-V to turn around and run back ...

I guess it is not about flying out to loot the enemy; the costs of getting anything usefull back would probably not justify an interplanetary (or interstellar war). Unfortunately this reasoning kills the space-pirate trope. And with them goes the necessity to patrol the space lanes for protection.

Anyway, I guess even with automated warfare sufficient story backgrounds can be generated to provide for thrilling adventures. Even if the attackers are purely automated, the suffering defenders will probably be human.

Anonymous said...

Byron said:"Ferrell:
I grow tired of this. Your scenario is contrived to make it seem that humans are needed. However, it relies on a long string of coincidences. You need a blockade, a hijacking (innocents aboard a vessel trying to break the blockade), and a high-thrust booster on the hijacked ship. Two stretch the limits of plausibility. The third is ridiculous. Claiming that this justifies humans is like claiming that because warships sometimes run aground, we should install huge external tires on all of them to help get them off.
All of the above even assumes that the scenario is possible under the laws of physics and how blockades will be conducted, which it isn't (though I won't go into that unless you insist.)"

Fine; by focusing on the details, you've missed the overall point I was trying to make; obviously that was my fault for not making it clear. The point was to merely illustrate that there could be situations where humans were needed in the loop closer than light-minutes, or even light-seconds. However, I see that I cannot convence you so, like you said, we should just drop it.

Now, as for deep-space combat; if you detect an enemy force comming toward your planet, then I think that a flyby attack, shifting from primarily missiles and kinetics while closing, to primarily lasers when the range starts to open up. Depending on how successful or not the exchange is for the defenders, there could be several of such flyby interceptions. Of course, any surviving units from the defender's flyby attacks would eventually return to the home planet. Whether those ships involved in the attack are manned or not, I think would depend on what is avalible and needed; I'm more certain that most ships in defensive orbit will be manned. Whether the attacking ships are primarily robots or primarily manned, really depends on their mission; is it invasion or bombardment?

I think that we are all getting bogged down in the details; I don't think it is a question of manned vs. robot, but what the mix should be and under what circumstances should the emphisis of one over the other be? Just like all warships should carry a mix of weapons, a space fleet should be a mix of manned and robot ships; the real question should be 'what should the mix be?'

Ferrell

Byron said...

Milo:
What about a ship that's entering the exclusion zone while loudly broadcasting an "aaaah, our engines are broken, help!" message?
Then they'd better have broken a long time ago. Ships will probably be told to keep course clear if close, and if it's not close, then you can dodge.

francisdrake:
We went over a lot of this already. I do like the chess analogy, but that's pretty much what I've been pushing for. What NativeJovian suggested is making your king a piece you have to use offensively. And it would also be clearly marked, unless you want to throw away 90% of the cost savings associated with drones.


But what if your robotic fleet has failed? What if the enemy prevails? Then you are closing in on the enemy, with lightly armed transports, with too little delta-V to turn around and run back ...

You just have to make sure this doesn't happen.

Ferrell:
I applaud you for trying to meet my challenge as to a scenario that would require humans. However, you seem to be under some misconception as to what I am proposing. Nowhere do I suggest that you should be more than a few light-seconds away. At that range, light lag is no greater than human lag. For example, verbally giving a short command, like "open fire" takes approximately a second. That is the same as the lag at .5 light-second range, which is the max effective range of Rick's SFnal laser from Space Warfare V. Human decison-making and order entry will dominate the lag at that sort of range.
While there will be a mix, I do not see any line combatants being manned. That is all I have been claiming. This afternoon, I'll try to go into more detail on how fast reactions need to be.

Byron said...

Reaction times and space combat timescale:
Some have criticized drones as suffering from excessive decision lag compared to a human crew. This is faulty, given the normal decision lag, and the timescale and nature of space combat. I will attempt to compare drones, crewed ships, and modern naval vessels.
Disclaimer: I am assuming that the drones are operating within 2 light-seconds or less of the control base throughout. Do not attempt to rebut using longer lags. I will be angry.
Despite extensive searching, I have been unable to locate conclusive figures for typical order reaction time on naval vessels. However, 30 seconds seems to be mentioned as a good benchmark to normal events, such as enemy missiles being detected. This probably stems from several levels of command, as well as from the basic time required.
Compared to this, both drones and manned ships should have improved reaction times, due to a lower number of layers of command to pass through. Often, the commander might either make the action, or give the orders directly to the action-maker.
If that cuts time in half, then a drone at 2.5 light-seconds will have a 33% slower reaction time than a manned vessel. At .5 light-seconds, probably reasonable battle range, the delay would be 6.67%.
This would seem to give an advantage to manned vessels. However, that ignores the structure of space warfare. Human instructions will be limited to what to shoot at, and where to go. And even then, they will not control the point-defense systems, except to set operating modes. In Space Warfare V, Rick's SFnal laser has a burn rate of 1mm of graphite every second at .5 ls. That seems a reasonable baseline for effective range. At that range, a farther 1-second delay in firing would likely be negligible. And that presumes a delay exists. It is likely that an automated shootback system would be enabled, particularly if a battle was about to happen.
As to steering, accelerations are so slow compared to distances that a few seconds will hardly be noticed. A ship at 1 milligee from rest will take about 48 hours to cross half a light-second.
Another objection is when shoot-don't shoot situations might come up, such as Ferrell's course-changing blockade runner. Again, these ignore the realities of space combat. Movement scales will be tiny compared to weapon range. Drones will almost certainly be empowered to shoot on threatening objects (CBDR, and it's following me). Things like exclusion zones will likely be large enough that even something on the other side of Earth's Hill sphere (10 ls across) from control should be able to be handled quite effectively.
In essence, thinking that every second matters is likely a leftover from terrestrial combat. Lasers can't be defended against, and likely aren't sudden-death weapons. Kinetic defense will be automated wither or not the ship is manned. Ships don't move fast enough to demand split-second decisions. In essence, a few seconds of light lag likely won't win or lose a battle.

Scott said...

My apologies if this is roughly a double-post, blogger glitched after auto-login and lost my comments.

a gunboat with a pilot/commander, sensor manager, and weapons manager. Maximum endurance would be a couple of weeks

Ok, I'll try to make a point again. The maximum effective watch length is 6 hours. Your efficiency goes to hell very rapidly after hour 6. This has been documented by every single navy that operates submarines.

So, let's make that ship capable of a week's operation: You will need 3 sensor techs for 24/7 operations. Your power supply will need monitoring, because computers are lousy for recognizing trends. There's another 3 crew minimum. As long as combat is only expected to last ~6 hours and you have lots of warning, you can probably get away with 1 weapon tech.

Now we're up to 8 personnel (3 sensor techs, 3 engineers, captain, and weapon tech). At this small crew level, you don't need a cook, everyone can do their own cooking. This also assumes that you don't need a 'pilot-in-command' or officer of the deck for legal reasons. If you do, then you would need at least one additional crew, total of 9.

Here's the bad part: how do you train the new guys? Add another 3 crew for trainees.

All this, just to get a ship not capable of flying to Mars under a vasmir drive without needing massive repairs when it arrives. (based on observations of Alfa-class subs time on station)

That doesn't sound real useful to me.

Scott said...

About maintenance requirements:

It has been my experience that something the complexity of a submarine requires about 250 man-hours per day of operation, for a 90-day deployment cycle, with a massive maintenance surge of about 6k-10k man-hours maintenance per day for another 30 days post-deployment. This makes the total maintenance required over 300k man-hours maintenance for 2160 hours deployed, roughly 150 hours maintenance for every hour deployed!

Note that this is within the examples of aircraft, too. F14 tomcats required roughly 70 hours maintenance per flight hour, while B2s require at least 135 hours maintenance per flight hour.

Tony said...

Byron:

"Message to everyone:
I have been claiming drones are the best option for deep-space fleet engagements. Nothing more.

Ferrell:
I grow tired of this. Your scenario is contrived to make it seem that humans are needed."


Pot, meet Kettle.

Tony said...

Scott:

"About maintenance requirements..."

+10

Also, WRT Byron's invocation of the Soviet Alpha class submarine's small, highly skilled crew, one should note that the Alpha was designed and apparently operated as an "interceptor" submarine. It would stay in base, where it could be maintained by a "ground crew", and only be used (on exercises or in war) to sprint out to the operational area, where it would operate for only a few days before sprinting back to port, where maintenance and reapir could be done before the next mission.

Now I know that someone will claim that RDs could be operated in a similar fashion. And with a certain ocerstock for maintenance float, that's true. But that means you have to buy and equip that many extra, and use that much more fuel/remass to move them on and off the patrol/battle line. I'm not seeing where we're gaining any efficiency here.

Tony said...

Re: laser accuracy and persistence

The Hubble Space Telescope has a pointing accuracy of 7/1000 arcseconds. That works out to a possible error of .034 meters at 1000 km. Doesn't sound like much, but we're talking about combat at light second ranges. At 1000000 km, or just a little over 3 light seconds, that's a possible error of 34 meters. That means that the beam from a weapon with near perferct pointing accuracy, against a nearly perfectly surveyed target, will wander around randomly inside a 34 meter diameter cirlce.

Against real military targets, whose position is not as perfectly known as an arbitrary point in the sky, firing from a weapon that is (relatively)rapidly slewing, that high level of precision actually becomes a liability. As is well know to students of naval warfare, imperfect knowledge of enemy position and motion (a given in combat, no matter how good your sensors are (even in space -- stay tuned)), combined with high pointing precision, leads to a lot of missing of targets. This effect was noted in combat at Jutland in 1916 and again at the Komandorski Islands in 1943. The British and Japanese gunnery, respectfully, were reported by their oppenents to produce small group dispersions. But because combat conditions led to less than perfect position and motion estimation, these groups much more often than not missed their targets. Both the Germans and Americans who were on the receiving end of this fire were of the opinion that more dispersed groups would have led to more hits on their ships. The principle is this: if you can't guarantee accurate targeting, some dispersion of fire is not a bad thing, because only a target in the impact area can be hit, no matter how small a percentage chance any given shot has of hitting.

WRT accuracy of target position and motion data, we're talking about ships that are intended for combat, whose designers and operators know will be exposed to hostile fire. They will be carrying enough reaction mass to jink under fire, then repair their trajectories after the battle is won. They will be equipped with powerful enough maneuving thrusters to jink quickly enough to make a difference. They will have military grade sensor suites, which means that they will see enemies that can target them, and start jinking in plenty of time to foul up targeting solutions.

I was asked a while back why I thought military experience is relevant. This is an example of why. Throughout all of these discussions, defense has been assumed to be impossible. But anybody with sufficient military experience could tell you that anything can be defended against that isn't an outright surprise. If he can see you, you can see him, and you have enough technical data to know when that becomes dangerous, nothing as mundane as the fact that he can theoretically hit you with a laser is going to be any kind of suprise at all.

WRT, the persistence of laser fire. Two things:

1. We now know that you have a jinking target that you can't accurately target. That means a pattern of distributed shots is the only way to get hits.

2. Spacecraft, even laserstars are not likely to carry sufficient power and cooling machinery for continuous fire. pulses are much more likely to be mechanically practical.

Anonymous said...

Tony; first: your analysis of space combat looks good; I agree with you on both technical and operational details.
Second: you've surprised me; you do have a sense of humor and I apologize for ever thinking otherwise. ;)

Scott: most of the electronics that I've worked with require Prevenative Maintenance at least once a day, and preformance checks every shift, with more serious maintenance about once a week; I would expect that a spacecraft engineering crew would be busy every shift doing some kind of cleaning, checking, adjusting, calibration, or minor repair whenever they weren't in actual combat. They might be the only members of the crew that aren't bored during normal operations.

Ferrell

Thucydides said...

Milo

A vehicle mounted surface to orbit weapon would be much smaller and less capable than a fixed installation; a laser buried inside a mountain could theoretically be powered by gigawatts of energy, but a scramjet vehicle mounting a laser might only end up with a small fraction of that. This might be useful for plinking spysats in low orbit, but not anything the main force in orbit would be too worried about.

Light hours is indeed the range the commander of the space force can start looking around, the resolving power of giant, high precision mirrors on board laserstars would let the commander start observing Mars before he even broke Earth orbit. In a Pournellian universe, once the Alderson point is secure, the fleet can start observing the entire solar system and use the laserstar mirrors for high resolution looks at points of interest.

This leads to an interesting implication; if there is no stealth and you can effectively "see" anywhere in the solar system, then would there even be military space systems at all? Probably the best thing to do would be to hunker down under a planetary surface or burrowed inside an asteroid with some form of thermal camouflage. Observation would be divided between human spies (diplomats, commercial travelers and "Impossible Mission Teams"), giant telescopes and "dark" robotic probes sheathed in metamaterials and only capable of very limited manoeuvring using electrostatic sails so not to reveal their presence. Maybe a space ICBM type force is really where things need to go...

Byron said...

Maintenance:
We've been over this, but I'll try to restate my conclusions in a more coherent way.
First, a drone won't have very many systems that need tending. Most spacecraft maintenance is going to be on life support systems. What is going to be running? Reactors (not crew repairable), attitude control (ditto), and a bunch of solid-state electronics (10 man-hours every 6 months). As to reactors, I'm fairly sure the one on NR-1 was not field-maintainable, and I know the Soviets had some up and working in orbit for over a year.

Tony, part 1:
I know the Alpha isn't a perfect analogy. I was using it to demonstrate that a large fighting crew isn't required.

Byron said...

Tony, part 2:
I fail to see what you're getting at with the example of Hubble. It's fundamentally different from a laser turret for several reasons. First, the mirror isn't independently steerable. It's like being able to point the entire vehicle to that sort of accuracy. Second, it's perfectly adequate for Hubble's mission, which is as a telescope, not a laser weapon. I have no doubt that we could pass it's performance if we had a reason to.

This effect was noted in combat at Jutland in 1916 and again at the Komandorski Islands in 1943.
That's interesting. I didn't know that. Thanks.

However, you again forget that we are dealing with lasers. Telling if it's pointing straight at the target is dead easy.

But anybody with sufficient military experience could tell you that anything can be defended against that isn't an outright surprise. If he can see you, you can see him, and you have enough technical data to know when that becomes dangerous, nothing as mundane as the fact that he can theoretically hit you with a laser is going to be any kind of suprise at all.
This is where your arguement falls apart. Yes, you won't be surprised when you get hit with laser fire, but you can't dodge, at least under plausible midfuture tech assumptions.
Math Problem:
You are in a 10-meter diameter laserstar, half a light-second from your enemy. He fires a laser at the apparent center of your ship. The laser is precisely targeted and will be infinitesimally thin when it reaches you. (I know that's not realistic. I'm doing a spherical cow.) How fast do you have to accelerate to cause it to miss in the one second between when he sees you and when it hits?
I'll post the answer in 24 hours or immediately after Tony's next visit to the board.
I'll leave the rest of the comment until after you've answered the question.

Mangaka2170 said...

The answer: at least 5m/s.

Byron said...

Not quite, but close. The answer needs to be an acceleration, though you did give the correct average velocity.

Luke said...

Tony:

The Hubble Space Telescope has a pointing accuracy of 7/1000 arcseconds. That works out to a possible error of .034 meters at 1000 km. Doesn't sound like much, but we're talking about combat at light second ranges. At 1000000 km, or just a little over 3 light seconds, that's a possible error of 34 meters.

The Hubble Space Telescope has an angular resolution of 0.043 arcseconds (more accurately, the Planetary Camera has a resolution of 0.043 arcseconds, the Wide Field camera has a 0.1 arcsecond resolution). That means that a beam projected using the HST as a beam pointer would have expanded to 210 meters across at 1,000,000 km (or, of more importantce to astronomers, anything smaller than 210 m at a distance of 1,000,000 km will be an un-resolved fuzzy blob rather than a sharp image). A pointing accuracy of 0.007 arcseconds is more than sufficient for the HST's needs, anything better would be a waste of resources. This is the point I was making earlier - the pointing accuracy of telescopes is greater than their resolution, so the width of the beam at the aim-point is larger than the uncertainty in the beam axis by a considerable margin. The uncertainty in the beam axis is thus unimortant - the position of the irradiated area is the same for all practical purposes.

Plus, there are ways to make the pointing accuracy better if you need to. The HST does not need adaptive optics - it is out in space where there is no atmosphere to mess of the light getting to it. But the same technology that gives us adaptive optics can also very rapidly adjust the beam axis to within a fraction of the beam resolution. There is no need to point the whole scope, just make minute adjustments to the pointing mirrors.

That means that the beam from a weapon with near perferct pointing accuracy, against a nearly perfectly surveyed target, will wander around randomly inside a 34 meter diameter cirlce.

A minor quibble unrelated to the main point, but I should make it nonetheless - this means that the beam axis will be at a random but nearly fixed point in a circle with a 34 meter diameter. (Even more pedantically, it will not be a circle, either, but will be a fuzzy probability distribution that could be better approximated by a Gaussian with a characteristic falloff of about 34 meters - but this is getting really esoteric.)

continued later due to length restrictions ...

Luke said...

continued reply to Tony:

Against real military targets, whose position is not as perfectly known as an arbitrary point in the sky, firing from a weapon that is (relatively)rapidly slewing, that high level of precision actually becomes a liability.

The thing about lasers is that they use light, and light takes the same path coming and going. Thus, if light lag can be neglected (more about this later), when the image of the target is in the central pixel(s) of the scope's detector, the beam will hit the portion of the target imaged in that center pixel(s). Physics guarantees this.

Now, this neglects light lag. For the HST used as a beam pointer, this is not an issue. The beam will be too wide to do much at those distances. Once the target can displace its position by more than its linear dimensions within the time it takes light to reach it, lasers are no longer guaranteed to hit. I think we are all in agreement on this.

You bring up the issue of slewing. This can be significant for nearby, fast moving targets, but not so much for distant targets, or for nearby fast moving targets that are moving nearly straight at or away from the beam pointer. For nearby, fast moving targets, you don't need as much resolution because it is nearby and your focus will be tighter. Thus, you can direct the beam through a smaller aperture but more maneuverable scope. For distant targets where slewing is not an issue you can use those big primary mirrors that people always get to whenever discussions on laser space warfare pop up.

The same technology that enables adaptive optics also allows active vibration control for the beam and its mirrors, so even a rapidly slewing scope can hold the beam axis to greater precision than the beam resolution.

They will be carrying enough reaction mass to jink under fire, then repair their trajectories after the battle is won.

This depends on both the drive system and the range of the laser. Every time I run the numbers, things look bad for the target if it is not too far beyond the range where hits are guaranteed - the necessary rate of propellant use is just too high and soon the target runs dry. Much farther out, things become different. At light hours distance, even very small thrusts will throw off the targeting sufficiently to make using the laser relatively futile (although if you are not limited by power you might as well leave the laser on if you have nothing better to do - if nothing else it will distract and annoy).

Now if you have a scenario at, say, less than a light minute range where plausible mid-future thrusters can evade a dangerous laser beam over tactically significant time scales without exhausting their propellant reserve, I would be interested to hear about it and discuss it.

Anonymous said...

(formerly just "Anonymous", now Semi-Anonymous Phil)

answering Byron - "what is that supposed to mean?"
-------------------
Only that if you can make a completely robotic spacecraft -- you could also make a "99%" robotic spacecraft with a crew of one human.

It wouldnt have many of the advantages (repair/flexibility etc) of a larger crew -- but it would be a crewed spacecraft with limited advantages over a 100% robot spacecraft.

========
As to the question by a later poster about 5000 crew aircraft cariers ... the biggest answer to that is R&D and Legacy technologies as well as demand for the said robo-carrier.

It would be possible in the plausible near future to construct and build a 100% remote aircraft carrier with 100% remote aircraft.

It would probably lack a lot of the capability and flexibility of the 5000 crew carrier, but with the right budget, it could be built, sure.

Its not a lot different from a 1000 person mechanized factory and a 100 person "fully automated" factory except in scale.

Byron said...

Luke:
Your analysis on jinking agrees wiht my own. I will have more to say after someone gets the correct answer to my question.

Phil:
If you are speaking of a long-term crew of 1 human, I don't see that as practical. I think that 30 is about the minimum crew for long-term operations. It's certainly more than a few.
However, a fighter-type ship, where the one crewman is carried aboard the tender until the battle might work. I'd probably put 4 or so guys aboard, but you could skip a bunch of accomidations if it's only for a day or two. That seems like a good idea for a story.

Anonymous said...

(SA Phil)

Seems to me the best way to handle the "Laserstar" Conjecture is to design a weapon system that has a longer effective range than the Laser's effective kill range.

Either that or build an even better Laserstar. Or throw away ones, which leads back to the Drone idea.

"Dodging" a lightspeed weapon within its effective range seems unlikely to be a high yield plan unless you have warp drive.

Byron said...

Phil:
I'd reccomend reading Space Warfare V, and probably the spherical war cows threads. It's a pretty good background for this.

ElAntonius said...

It's actually not all that different from "evasion" of weapon fire today: pretty much every weapon in use today has performance characteristics that make it inherently undodge-able by their intended target.

There are exceptions, but for the most part fly-boy hijinks to dodge missiles or last second bullet dodges are the stuff of cinema.

The problem with posting your crew (say) one light second away is that they aren't safe in that scenario. If the drone(s) associated with them go poof, then they're vulnerable, but worse is that there's nothing really stopping the opposing force from just attempting to push through and kill the CIC ship(s), effectively beheading a fighting force.

On Earth, where CIC functions can be far away AND concealed, this isn't a big deal, but in space the CIC ships will be big glaring targets, armed or not.

I'd imagine the real solution is small, distributed crews...someone mentioned a crew of 12 as a reasonable minimum, which matches my gut as well, relying on automation to run most of the decisions but preventing "home run" style strikes from handicapping your fighting force entirely.

This presumes you need humans in the loop somewhere to operate the spacecraft...obviously if they're capable of completing the long term mission without any human interference I'd wonder why there's people amongst the fighting force at all.

Byron said...

ElAntonius:
Why isn't a crew safe a light-second away if the maximum weapon range is .5 light-seconds? If the drones are dead, then they've lost. Period. The crew would be just as dead if they had been in the combat ships. While the command ship might be a big target, lasers won't be able to get at it, and kinetics will be detected a long way out. Also, they will take quite a while to get there, probably not tactical timescales. And even a crew of 12 (which I think is too small for long-term use) is going to be a pretty big penalty for most tech assumptions.

Anonymous said...

(SA Phil)

Byron,

Yeah that 1 person is going to go crazy but humans have done long missions solo. Look at solo Atlantic crossings or around the world sailors.

Several months would not be impossible if there were sufficient need.

Every person you add makes it that much more effective to an extent. several multi-year Real World expiditions had crews in the 4-10 range.

It would be a mass vs effectiveness trade off.

ElAntonius said...

Byron: I disagree that 12 is too small for combat operations, but fundamentally I don't think the number is really a source of contention and I'm willing to move on from it.

My real point is decentralizing the CIC process, because the first instinct on a drone led army is going to be to knock out the CIC ship (that goes triple if the drones need explicit weapons-free orders from the CIC ship). The drones might already have their orders set for the battle, but without a CIC ship they might be unable to continue their original mission.

Don't get me wrong, I agree that humans don't really need to be in manual control of all tactical functions for deep space fighting.

I think it's difficult to define a "safe" range from a space battle...what are the closing rates vs. the closing ranges? Does tech allow for multiple passes? Are weapon strengths such that everyone dies on the first shot?

For that matter...what are people fighting over in deep space? A defensive intercept could probably be safely all robotic, but the offense is a whole other matter: what do they plan to accomplish after they win the battle?

Fundamentally, if maneuver is not a tactical concern then the "penalties" of having a small human crew are not nearly as glaring...sure, each individual ship will mass more and require more propellant, but what is the extra performance buying for the RDs? I've already accepted that jinking is pretty much useless at those ranges, so we're left with a cost argument. That's meaningful, but then it gets into things about economic parity and who the attacker and defender are. Additionally, is one (say) 100 man people carrier and 10 drone laserstars cheaper than 10 10-crew laserstars? The argument really favors the drones if you can do a much more limited crew on the CIC ship, but the scope of my argument is restricted to decentralization.

My whole point is that distributing crews makes more sense if they're in harm's way due to the battle, because otherwise you're vulnerable to "knockout" blows.

In either case, I think planetary conquest is rightly impossible from space, so I tend to think that most interplanetary warfare will be conducted via robotic missile missions that target planetary installations, with defensive interceptor missiles playing the other half.

I just don't see a role for Deep Space Fleet on Fleet battles in the plausible midfuture, manned or not.

Rick said...

If you were constrained by known laws of physics, then you wouldn't have an operatic interstellar-empire setting.

Tough crowd, tough crowd! But my 'known laws of physics' proviso applies to the battlefield setting, not every aspect of the setting. Let's face it, a common 'hard SF' trope (and also my own bias) is to have a lot of realistic sounding space tech, combined with the story scope of FTL.

If ships are fighting in hyperspace, it is a whole 'nother game than what I've been discussing here.


My general contention here is that space combat, at any rate demi-realistic space combat, is weirdly different from terrestrial combat, to the point that much of our military experience is thrown into doubt.

My thinking on laser combat is centered on relatively modest tech assumptions - wavelengths near the optical band, zapping through telescopes at targets less than a light second away, say 10,000 to 100,000 km. If you have X ray lasers with multi-meter apertures, things get much worse!

But even at these 'modest' ranges, the tactical geometry changes only very slowly, even if you have torch level drive performance. Conditions are radically unlike naval gunnery in any era.

Maintenance is a very major question. But it seems to me that key systems, notably reactors and pretty much all of the propulsion system, are not available for onboard maintenance in any case, while some large proportion of naval maintenance tasks are broadly related to life support. (Including the extremely corrosive environment of salt water and oxygen - conditions favorable for human life, but lousy for equipment.)


Somewhat meta, but the arguments I've been making in these posts are NOT so much my own biases as positions I've been forced to. The image of space warfare I used to have was quite different!

Byron said...

ElAntonius:
The problem with "Let's knock out the CIC ship" is that that's similar to the Japanese in World War II saying "Let's knock out Nimitz's and MacArthur's headquarters." A nice idea, but if the people in question are doing their jobs, impractical. And yes, I do know about Yamamato. That falls under not doing their jobs.

As to the penalties of a human crew, I agree that it might not make much difference tactically, but strategic manuver will be a different story.
If we look at what I'll call basic payload (no engines, tanks, or armor) then a human-crewed ship's will be larger than a drone's perhaps significantly. The rest of the stuff will scale with basic payload. If the humans increase BP by 10%, then the entire ship's mass will be 10% greater than an equivilant drone. I expect that the increase will be larger, and I'm deeply skeptical of crews smaller than about 30 for extended missions, and I expect that the CIC ship will be able to get away with a lot smaller crew than a warship. You only need one guy per drone, remember.

Rick:
That's pretty much true on tactical geometry. However, one thought. Torch drives make dodging much more practical, thus forcing ships to shorter range, where the geometry can be changed on moderately reasonable timescales.

Byron said...

Command ship vulnerability:
Several people have raised the prospect of attempting to decapitate the drone force by taking out the control ship. However, the exact means have not been specified.
For purposes of this analysis, I will assume that the enemy force is .5 ls from the drones, which are .5 ls from the control ship.
The primary weapons in space are of course lasers and kinetics.
Lasers:
I will again use Rick's SFnal laser (the UV one) from Space Warfare V. This is to eluminate any suggestion of bias, as that was posted long before I came here. It has what I would describe as an effective range of .5 ls. Any shooting at the command ship will only dazzle it. That might seem to give you a combat advantage, but at the same time, the drones are shooting at you and doing damage. Remember that lasers are governed by the inverse-square law. Shooting at the drones is likely to do more damage, and the control ship can just back off out of range.
Kinetics:
The problem with kinetics is that they make poor tactical weapons at light-second ranges. To make a 100 km/s coilgun, the gun itself would have to be 100 km long according to Luke. That seems a bit implausible. While length scales with the square of velocity, I can't see any practical coilguns with higher velocities than 10 km/s (1 km long). Missiles suffer fromt the same issue. Any drive that can make a velocity that is tactically useful is either low-thrust or falls outside the plausible midfuture.
Even at 100 km/s, it will still take 50 minutes to transit a light-second, including going right past the drones, who will undoubtedly shoot at the projectile, and alert the control ship to its presence. The control ship has all that time to dodge, and can ready its own defenses.
In conclusion, I fail to see that the control ship is vulnerable to a decapping strike. If the drones are destroyed, then the battle is lost anyway, and the ship can hang back far enough to avoid fire.

ElAntonius said...

Byron: The problem with "Let's knock out the CIC ship" is that that's similar to the Japanese in World War II saying "Let's knock out Nimitz's and MacArthur's headquarters." A nice idea, but if the people in question are doing their jobs, impractical. And yes, I do know about Yamamato. That falls under not doing their jobs.

Is Yamamoto some sort of space battle Godwin? :P

Maybe the disconnect here is in assumptions. I tend to take a rather dim view of deep-space combat, and my tech assumption here is that you're not going to have battle fleets flitting around the solar system...in my assumption, one of the few missions I can think of is "boot to Mars, destroy as much orbital infrastructure as possible, boot back". With a CIC ship it's true that you don't have to boot the drones back, but conversely, lasers are expensive and I can see why it might be desirable to have the drones back (if only to not leave them Martians with a bunch of ready made Laser Stars parked in orbit).

I'm actually putting a bit of a devil's advocate hat on here...as I said in my previous post, I think it makes more sense to just send an all-robot missile massacre if you want to try to ruin a planet's day.

While I'll concede that it's possible that 1ls away is "safe" on tactical timescales, in a strategic sense it's still a risk of personnel, so I don't think a CIC ship buys much (if anything) in terms of safety.

This assumption goes right out the window if the CIC ship can just turn tail and run away reliably, of course.

As to the penalties of a human crew, I agree that it might not make much difference tactically, but strategic manuver will be a different story.
If we look at what I'll call basic payload (no engines, tanks, or armor) then a human-crewed ship's will be larger than a drone's perhaps significantly. The rest of the stuff will scale with basic payload. If the humans increase BP by 10%, then the entire ship's mass will be 10% greater than an equivilant drone. I expect that the increase will be larger, and I'm deeply skeptical of crews smaller than about 30 for extended missions, and I expect that the CIC ship will be able to get away with a lot smaller crew than a warship. You only need one guy per drone, remember.


I tend to think battle missions will be one shot: loitering around a hostile planet will be impossible. (A planet is just too hardened, at least if the have the resources to build defensive constellations).

Maybe that's the problem: for the set of assumptions I'm operating on, I acknowledge the disadvantage of crewed ships but just don't see it as a factor.

In my mind, if you can afford to have the crew 1ls out, you can afford to have them on Earth (or in orbit around Earth or whatever). If you need boots on the scene, you might as well put boots on what you're sending, because once you commit to a manned mission you have to pay the piper one way or another.

I'm still assuming heavy automation on the laserstars anyway, so my assumption is that a laserstar with RD tech needs only 1 active combat crew to actually fight with it, be they onboard or not.

Byron said...

ElAntonius:
I see we're headed into dueling assumptions again. I'd rather not go there. I already did this with Tony.
I'm still assuming heavy automation on the laserstars anyway, so my assumption is that a laserstar with RD tech needs only 1 active combat crew to actually fight with it, be they onboard or not.
That's one of the big advantages of the command ship. You can cut your manning requirements, probably significantly.

As to risking the crew, you gain three benefits from drones. First, there's less total personnel deployed, because of centralization. Second, if you lose the command ship, the battle is lost anyway. There won't be personnel lost with the drones you lose when you win. Thrid, the command ship will likely be allowed to surrender if it loses. There's no real reason to destroy it if the drones are all gone.

ElAntonius said...

Byron: You posted your math on decapping while I was busy with my response, so I'll get that now.

FYI, I'm not worried about "bias". We are, after all, discussing fiction...the author is free to make whatever tech assumptions they need to to create the scene they want (hell, the SFnal laser is itself a pretty huge assumption).

The problem lies with relative vectors...assuming the two constellations are closing head to head, is the laser tech high performance enough to decide the battle before one side's offensive capability is disabled? If it isn't, then decapping is a valid tactic. So basically it comes down to whether a fighting force is totally eliminated in the first pass.

Byron said...

Remember one fact about lasers. They get more lethal at close range. I seriously doubt that most non-orbital battles will go to multiple passes, simply because lasers will increase in power at close range, and kinetics come into play at about the same point. I suppose it could happen, but I find it unlikely. Plus, the command ship could be off to one side or something.

ElAntonius said...

Byron: Don't get me wrong, I'm actually trying to work within your assumptions, not trying to present my assumptions as the one true way. My point was to try to get you to expand on them (I don't mean tactical assumptions, I mean strategic and logistic).

Let's assume, for the moment, that the battle is complete...can you answer what you feel about:

1) Are the CIC ships on both sides survivors?
2) Does the loser have any fighting capability left whatsoever?
3) If the offense was the winner, what is their objective that they are now free to pursue?
4) Did keeping the CIC ship safe require the burning of remass to keep it out of the fight until it was over?

The thing is, the more thought I put into this the more I'm convinced that where humans are located in the scenario is wholly dependent on a higher view than tactics, so I'd like to lay out on the table what the 10k foot view is on technology and mission profiles before we go farther.

Byron said...

1. I would assume that CIC ship survival is probably normal, unless one side makes it a special project (take no prisioners). It shouldn't be too terribly hard to set your trajectory so that if the enemy wins you don't end up in teh middle of his fleet. And if you lose, then just surrender.
I'm not sure the sides will want to close to point-blank range. They might go by at a max seperation in the .1-.25 ls rang. That would probably allow both control ships to evade the other side later.
2. The loser's fighting capability will likely depend on the type of battle. If they go by at point-blank range, I expect that both sides will be really beaten up. It will probably lead to a tactical draw, with whatever strategic effects might flow from that, unless one side has a fairly heavy overmatch.
If the battle is at longer range, the loser will likely still have ships. Plus, I expect there to be a couple of guards for the CICs.
3. I'm not sure. Securing control of the defender's orbital space would be a good example. This might be a case where the defender loses, but weakens the attacker's force enough to make it impossible to sieze the planet's orbit.
4. Most likely. Some level of remass burn is inevtiable. It's entirely possible that the CIC could be headed the other way during the battle, along with a couple of tankers. If they win, refuel and turn around. If they lose, keep going.

Luke said...

Some thoughts ...

Regarding maintenance: We have two models to use for the maintenance needs of combat space drones. One comes from terrestrial combat, where fighter jets and naval warships need extensive maintenance. The other comes from science space drones, such as Cassini and Galileo, which operate with a large ground crew but which also operate for years with no maintenance and without mission-threatening malfunctions. Of course, some science space drones do fail. Sometimes this is due to problems with the ground crew (like mixing up metric and imperial units, ugh!). Other times it is due to manufacturing flaws (such as Hubble Space Telescope's warped primary mirror) which can be corrected if maintenance is available. And there are other examples where the failure mode is unknown (Beagle 2).

Which model is appropriate for space combat craft? No doubt people with military experience will fall back on the military model, while those more familiar with science will fall back on the science probe model. Does anyone here have any good arguments why one of these models is more likely to be applicable than the other?

Regarding the command craft: I do not see much use for offensive weapons on the command craft - that's what drones are for. I expect the command craft probably would have small, low delta-V seeker heads whose purpose is to interpose themselves between the command craft and incoming kinetics. These would be cheap and effective at antimissile defense. If the command craft feels the need to have lasers for defense, it would be more effective to have a drone laserstar hang back so that the command craft is within its engagement range, and then have it lase incoming kinetics.

The time scales for solar orbital maneuvering are long - on the order of days, weeks, and months. For this reason, there can be a very long stand-off distance between the command craft and any kinetic buses. The command crew assigns each kinetic bus its targeting priorities and then sets them off. If necessary, they can update their commands as conditions change in the subsequent weeks until the engagement, but the flyby part of the engagement will occur so rapidly there is little need to have oversight at this part of the combat. The command craft can sit back comfortably light minutes or light hours from the actual conflict. This raises the question as to whether the command crew needs to be in a spacecraft at all for kinetics-only combat. Perhaps if the kinetics are merely to clear the way for a planetary blockade or bombardment a command craft would be needed, since once you get into orbit high level decisions need to be made.

For lasers, the situation may be different. Until the laserstar gets close enough to resolve its target, the command crew will only be able to guess at what vulnerable surface installations are present, and what priority to lase them in. How far back you can be and still make meaningful decisions will depend on your tech assumptions (particularly sensor resolution), but I doubt the command crew need get closer than a few light seconds. They could receive the video feed from the laser star and assign targets in a reasonable time frame.

It would seem to me that the reasonable tactic is to have your drones meet the other guy's drones far enough away that your command craft cannot be directly targeted. That way the other guy has to fight his way through your drones before he blows up your human crew. In addition, having pre-programmed sets of priorities for mostly autonomous drones reduces the incentive to blow up the command craft - if the drones receive no further information they will continue with their last orders. This means that not only will blowing up your crew not incapacitate the fighters, but if the other guy blows up your command crew his command crew cannot surrender if his drones lose!

Milo said...

Thucydides:

"Maybe a space ICBM type force is really where things need to go..."

The problem with those missiles is when they reach the target planet.

Unless you have antimatter missiles that can blow the planet asunder, you're going to be trying to hit specific targets on the planet, which are likely to be moving and/or camouflaged. And planets are cluttered environments.

The best use for interplanetary missiles in space would be defensively, to intercept an incoming attack force.



Luke:

"At light hours distance, even very small thrusts will throw off the targeting sufficiently to make using the laser relatively futile"

Once again, lighthours distance is all the way across the solar system. Any weapon capable of causing meaningful damage across this distance would totally change space combat, even if it has poor accuracy. (Remember Tony's comment on how a weapon with poor accuracy will still hit if you make enough shots.)

I would already be very impressed by any weapon that can hit across lightminutes.


"(although if you are not limited by power you might as well leave the laser on if you have nothing better to do - if nothing else it will distract and annoy)"

Wouldn't keeping a weapons-grade laser running for days on end degrade your optics?



ElAntonius:

"For that matter...what are people fighting over in deep space? A defensive intercept could probably be safely all robotic, but the offense is a whole other matter: what do they plan to accomplish after they win the battle?"

Any battle in deep space is probably either a defensive intercept, or an ambush to attrit enemy forces / preemptively disable would-be defenders before they can take up their defensive positions. (Say you control two planets, Venus and Mars, and I want to conquer Mars. I see you sending a reinforcement fleet from Venus to Mars. I decide to intercept the fleet in order the destroy it in a comparatively easy fight where I don't have to worry about surface defenses or the ships that were already at Mars.) It might also be a pirate action aiming to capture valuable resources held by the enemy convoy (or rather, privateer action, since we've established that piracy in space is pretty much impossible without having a stronghold to retreat to afterwards).

Of course, it should speak for itself that only one is seeking to intercept. The other side would have been hoping against a deep-space battle, but failed to prevent it. Their primary mission could be anything, but is likely to revolve around a planet somehow (although it could be a different intercept), meaning that their deep space combat capability is there purely in an escort function.

As for what the fleet plans to do after winning, in the case of an intercept mission, they'll likely just return home, refuel, and (if crewed) spin tales of their heroic exploits over at the spaceport bar until they're called on again. In the case of offensive action, they'll likely enter orbit around some planet and start blockading, bombing, or landing troops.

Milo said...

Byron:

"Shooting at the drones is likely to do more damage, and the control ship can just back off out of range."

Umm, how do you "just back off" in space? You were just talking about the difficulty of making large sudden velocity changes with a rocket.

Anyway, the control ship would already be at the largest distance that it can while still being combat-effective. If it could afford to back off much more, it would have already done so.



ElAntonius:

"I tend to think battle missions will be one shot: loitering around a hostile planet will be impossible."

You can wait in high orbit. Earth's Hill sphere is 5 lightseconds in radius.



Byron:

"As to risking the crew, you gain three benefits from drones. First, there's less total personnel deployed, because of centralization."

But one of the arguments for needing large crew sizes is that you need separate people watching each post and device. If you need a separate person watching each sensor system, then you certainly need more crew members the more drones you have to watch out for, even if they're all in the same place.

ElAntonius said...

Byron:
1) That might make for a interesting/depressing warscape, where the combatants escape relatively unscathed most of the time but now there's a fleet of ravening death beam ships heading for a planet.

Probably make for a good anti-war story, actually.

The reason I ask about CIC survival is because if CICs are expected to escape or be captured, then there's a corresponding higher value on their lives...as such, war will be more "gentlemanly".

2) That's what I was pondering as well. Ignoring the discussion of manned vs. unmanned, it strikes me that most space battles will be tactical draws with strategic victory for the defender, unless the attacker uses overwhelming force.

Assuming technological parity, once things get into kill range I think a lot of ships will die on both sides.

3) Is really what bugs me all about. For a planet to have a sizeable battle fleet, I think it needs to either have support from Earth (in which case a countersiege will be launched by the host country) or needs to be as developed as Earth (in which case it's really just an orbital stalemate, with ASATs holding the ships from doing much real damage).

The only real scenario I can think of is blockading an Earth-like planet to prevent it from supplying or reinforcing dependent colonies while they get conquered one by one.

4) Plays with 2. I'm wondering if it's possible to have a victor at all, really, since all I can picture is that even an eliminated defender force is liable to force a mission failure.


Luke: if you're going to have a drone hang back to protect the CIC I'd imagine it's easier to just attach a hab to a drone and have that one ship hang back. Personally I agree with your post: I think any CIC isn't going to be light seconds out, it'll be light minutes out, well away from any fighting.

Byron said...

Luke:
I don't think we really can know what maintainence model will be used. We have to guess. My guess is obvious.

Milo:
Maybe I could have phrased that better. The point is that attempting to attack the command ship with lasers is going to be a losing battle.
As to crews, if I need 18 (compromise number) per ship, or 4 per drone, which gets me fewer people?

ElAntonius:
I do see this sort of war as being fairly gentlemanly. This is particularly true if it's war between colonies which are both short of skilled personnel. They want the other people alive for later when they've won. (See below for more on this)

On a slightly larger level, it strikes me that a degree of ruthelessness will be very useful. If I'm willing to automate my blockade drones, and take the chance of a PR hit, I gain a significant cost savings. Ditto if I'm willing to be slightly indescriminat during the bombardment in support of my invasion.

On an even larger level, a common problem during these sorts of discussions is the dominance of Earth. It's so powerful that it's hard to construct a plausible scenario for equal powers engaging in deep-space warfare. One solution to this was AV:T, and another was my Rocketverse. Both got rid of Earth to make it more interesting.

Milo said...

Byron:

"As to crews, if I need 18 (compromise number) per ship, or 4 per drone, which gets me fewer people?"

Why do you need less people for drones than ships?

All of the same decisions still have to be made, even though they're being made in a different place. Having all people on one ship limits the size of your maintainance crew, but that's because you're doing less maintainance, which isn't actually a good thing (except when it comes to life support maintainance).


"On an even larger level, a common problem during these sorts of discussions is the dominance of Earth. It's so powerful that it's hard to construct a plausible scenario for equal powers engaging in deep-space warfare."

America started as a British colony, and only took a few centuries to build itself up to the point where it's the world's undisputed superpower, while Britain is languishing.

Now, developing another planet to that point will take somewhat longer, since there's a bigger area you need to work on, and you start with less (America already had air and arable soil - and people, for that matter, but the colonists didn't care to keep those).

But I think it's not unreasonable to have well-developed planets or moons in any midfuture that takes regular space travel as a given.

The biggest problem is terraforming. It's not gonna be easy, no matter what.

Byron said...

Milo:
Why do you need less people for drones than ships?
Simple. If I'm going to put people on a ship, I'm going to do it right. I want the ability to deploy it independently. What am I going to need for a basic ship? 4 officers, 4 sensor techs, 4 helmsmen, 4 mechanics, etc. On the other hand, putting them on the mothership means I need maybe 4 drone monitors and a mechanic. The same number of decisions get made, but I have a lot less people who do support stuff.

Luke said...

Milo:

Wouldn't keeping a weapons-grade laser running for days on end degrade your optics?

For the specific case mentioned of lasing at at target light hours distant, with microgee target accelerations you could plausibly be looking at keeping the laser running for years on end.

As for damaging the optics - for near visible radiation you could probably design cooling systems to keep the optics happy. Light hour ranges probably imply x-rays, though. I am somewhat less familiar with the gritty details of x-ray optics. I know that modern synchrotron x-ray optics can handle blow-torch intensity x-ray fluxes, but for all I know they may require frequent maintenance. If you are getting light hour ranges using gamma rays, you are already using magic for your focusing optics so you can use authorial fiat as to whether they can withstand the heat (although zone plates will work with gamma rays if you can make them thick enough. I can't think of anything else that will).

Scott said...

About crewing numbers: my rough-guess of a 9- to 12-man crew was for the equivalent of an Avenger torpedo bomber with a greater-than-12-hour deployment range!

No doubt people with military experience will fall back on the military model, while those more familiar with science will fall back on the science probe model. Does anyone here have any good arguments why one of these models is more likely to be applicable than the other?
The total number of systems (and moving parts) involved.

How many systems are there on Hubble? Power generation, attitude control, data transciever(s), Gyro, and 3 cameras. Of those 6+ systems, how many moving parts? (power generator, 2; data transcievers, 2 per or so; Attitude control, many valves; gyros, many)

How many systems are going to be needed to get a functional laserdrone with one big beam, no missiles or point defenses? Generator, main engine, attitude control, beam generator, search systems, tracking system, beam pointer. That's the shortest list I could come up with.

I can't even count how many moving parts there are with 7 military components versus 7 scientific components.

We all agree that moving parts will (eventually) break, and that broken parts are at least a mission-reduction, if not an outright mission kill. Ergo, maintenance is required.

Most spacecraft maintenance is going to be on life support systems.

Most of the maintenance that we did on the sub was not atmosphere monitoring or control equipment. It was mission equipment, with life-support stuff a distant third behind power generation.

a drone won't have very many systems that need tending

Electrical generation needs tending if you have varying loads, like starting and stopping remass pumps, chem-laser fuel pumps or mirror-pointing motors. The more electrical power you need to deliver, the more important it is to monitor.

And while nuclear reactors are not field-maintainable, the generator systems are.

Rick said...

How does the ISS compare in complexity and moving parts to a sub? It has been kept fully operational over a period of years with an onboard crew of 3-6, and no port calls.

It is an odd example since it is the only long duration space mission that does have a crew, but it should say something about our ability to build large, long-mission spacecraft that need relatively little human maintenance.

Scott said...

How does the ISS compare in complexity and moving parts to a sub? It has been kept fully operational over a period of years with an onboard crew of 3-6, and no port calls.

Well, mechanically simpler power generation to start, with 2 moving parts instead of hundreds. Smaller generation capacity, too. No high-pressure gas systems (subs have at least 2). No hydraulic systems, but that's not likely to be an issue in space.

No Hubble-equivalent detection system, let alone 6 or more like a sub carries.

No weapon systems, no fire control. No self-protection systems, either.

No main engine, no automatic attitude controls that I know about.

That's just the top-of-my-head list.

And finally: Yes, you can make things 99.99996% reliable (good lord, I just invoked 6-sigma). The cost increases by an order of magnitude every decimal point of reliability increase. If 99% reliable is a million dollars, 99.99996% reliable will be about 10 Billion. How much do you want to spend?

Tony said...

Let's see...

1. Jinking is not dodging. It's a term that comes from AFV combat -- vehicles maneuvering within the field of view of enemy weapons capable of damaging them are turned at random angles, at random times. This causes range and motion inaccuracies within the enemy's firing solution, because he can't process information instantaneously. This principle applies to any targetting situation in which the potential target has maneuvering capability. The idea is not to get out of the way of known incoming fire. The idea is to make any immediately good solution invalid by the time the weapon can strike. At the range of three light seconds for example, a jink has quite a lot of time to take effect, even with laser weapons:

3 sec (target to sensor)
? sec (sensor integration + decision processing + weapon actuation interval)
3 sec (muzzle to target)

Say 7 seconds. A jink that moves the target spacecraft 100m in that time only takes an impulse of 15m/sec (1.5 g) for one second. That's a lot of power, but we're notionally talking about spacecraft that can fire a combat effective laser pulse 1 million kilometers.

2. The relevance of the Hubble example is to demonstrate how inaccurate the most accurately pointable space device can be. And this level of accuracy is only achievable with high-precision, low-vibration pointing gyros, and, I failed to mention earlier, after an amount of time has been allowed for induced vibrations and changed haeting profiles to settle down. With combat systems, under combat conditions, I doubt you could come anywhere close to that level of pointing accuracy. And asserting that it could be done if it needed to be is meaningless hand-waving.

Also, nota bene, there has been an ongoing assumption of perfect sensor alignment, perfect translation of the raw data into actionable information, and perfect boresighting of the weapon. These aren't suspect analogies from irrelevant terrestrial military experince (though the terminology partially emanates from such experience). These are issues of mechanical precision that effect any integrated weapons system. I have no polite terminology with which to address such assumptions. Sorry.

3. WRT maintenance, I have to second Scott. Most maintenance is on mission-essential systems, very little on life support. Even surface ships have life support systems, in the form of food service equipment and food storage systems, not to mention the food itself; sewage storage and dumping systems; fresh water production and distribution; lighting; intercommunications; and a host of more minor things. About the only thing missing is pressurized breathing gas -- but ships do maintain and operate air conditiong, which is analogous in all but air gas storage.

Still, these do not demand a big part of the crew's attention. It's all the rsponsibility of the auxiliary machinery division, which is a small part of the engineering department on most ships.

Byron said...

Maintenance has degenerated into purple vs. green. I don't think we'll agree on that.
As to laser accuracy, Luke knows a lot more about it than either of us, and he seems to think it will work.
And particularly if your theories on lasers are correct, is anyone going to bother shooting at 3 light-seconds? That makes no sense given your assumptions.
Also, you make 1 G sound like a little bit. It isn't. That engine will take a considerable amount of your dry mass, and it won't be terribly effective closer in.
As to my math problem, are you going to solve it, or not?

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