Comments on Rocketpunk Manifesto: Space Warfare VII: Kinetics, Part 2 - The Killer B...

Previous comments-WOW! If kinetic warfare at long ...

2010-08-02T14:11:49.567-07:00

Previous comments-WOW! If kinetic warfare at long ranges leads to an escalating frag vs frag conflict, it could easily turn into two WWI biplanes trying to dodge clouds in a storm :/

Rick-Electric Ion drives being used as powerplants for a laser is another example of redundancy that Hard Sci-Fi likes.
However, in a midfuture setting, where torch drives are used, I'd see kinetic weapons as more of a 'military thing' than lasers. A cargo ship just hooks up its drive to a laser and presto it has a MW weapon. Kinetic missiles are HEAVY, cutting into Delta v budget and the merchant's pockets. Economically, a KKV bus is more akin to a Tomahawk strike today (if you get my drift), than an AMRAAM.

I see my KKVs not leading into larger and larger spreads of shrapnel, covering a larger and larger area, but into more and more precise impactors.
Example:
-THE BURN STAGE:The initial bus sent from the warship is a nuclear thermal rocket that increases its temperature until maximum acceleration/drive meltdown. This gives the whole bus say +10km/s relative to launch craft.
-THE EW STAGE:This divides into say 10 missiles each with a targeting system that does up to 10 course-correction burns before splitting into 100+ shotgun-rockets.
-TERMINAL STAGE: The resulting 1000 little rockets (1 meter each, 200kg) are all travelling at roughly the direction of the trarget. Those too far away explode and release their shrapnel anyway into a sphere. Those within the manoeuvre cone do a final correction burn and explode.

There!

Luke - Good points about drive power and beam powe...

2009-08-30T17:29:30.122-07:00

Luke - Good points about drive power and beam power. I forgot that an externally powered electric drive could indeed put its full reactor power into the laser, and get a fair fraction of it as zapping power.

Power density limitations - i.e. not wanting to melt your laser - mean that a laser installation like that would be pretty massive, and surely keel mounted.

On wartime tech developments, I can see an upcoming blog post here. A couple of points I'll add to the mix. In World War I new aircraft were sometimes developed and deployed in a matter of months. In the earliest stages of a military tech you are more or less throwing things together off the shelf, so crude weapons could proliferate quickly.

And taking up on what Ian said, in the 19th century military tech followed rather than leading industrial tech. So it is not just a matter of mature techs. I agree that military procurement won't necessarily follow the patterns we've seen in the last century. There's a wide zone between everyone singing 'Kumbiya' and intense 20th century style militarism.

I would say concepts for new weapons are born only...

2009-08-30T14:52:51.952-07:00

I would say concepts for new weapons are born only during wartimes, it is after the war when they are improved and set ready for the next war, where they will be decisive:
Tanks were entirely developed during WWI. And Allied forces fielded them in important numbers at the end of the war. Of course it was not an important weapon until the next big war.

About killer-buses: Interesting idea. It seems to be some equivalent to a modern day long range antiship-missile. Wheter it will be an important weapon will depend on multiple variabels.
I think pure warships will have at least some use: How do you hold your recently adquired "territory", after all you may want to be able to use space as safely as possible while at the same time negate acces to it to your enemy.

That's the modern pattern of constant tech R&a...

2009-08-30T14:01:37.253-07:00

That's the modern pattern of constant tech R&D, but there's no guarantee that future politics or military procurement will support it. Right through the First World War military development worked on (Roughly) the pattern I described: Making it up as you go along. This is probably the typical pattern for technological plateaus - Eras of incremental technology change rather than our divergent era of rapid development and deployment. Singularitans aside, there's no real reason to believe our current pattern will continue into the future. All of the weapons systems we're talking about could be built with current technologies if we really needed to.

Our current rapid R&D/deployment cycles are also political, a continuation of the 20th Century's post-First World War arms escalation. Political regimes that valued stability over brute-force statecraft could put military development behind terraforming, developing the outer system's resources, or make-work projects on Earth.

This takes us to the point that we need to know what the political system is, what resources they have, and what they consider worth fighting over before we can really argue over the 'best' weapon systems. Otherwise we're just redeveloping current doctrine (Aircraft carriers, smart missiles, and drones) for space.

Ian_M

As I said, those weapons (jet fighter and nuclear ...

2009-08-30T13:07:24.241-07:00

As I said, those weapons (jet fighter and nuclear bombs) were under development from before the second war and actually the research started in the inter war period. Yes once a weapon is fielded in a war the deigns will change again. That's the part called field-testing.

For example after the Koran war--where missiles saw tentative first uses--the USAF thought guided missiles would be the end-all of aerial warfare. In Viet-Nam they discovered that they were a lot less accurate than predicted. The F-4 Phantoms, which were a missile-exclusive weapon, were retrofitted with *guns* to dogfight the MiG-15 because the slippery buggers could ditch guided missiles too easily and the had to be shot down. After Viet-Nam they went back to the drawing boards and redesigned the missile guidance systems, culminating with the likes of the AMRAAM and even the Phoenix which could shoot a fighter down at 300 miles. Yet the F-14, which mounted said Phoenix, was still armed with a 20mm cannon. Lesson: learned.

My point was exactly this: each war shows us how weapons behave under real conditions. In the pause between wars, the weapons are redesigned for the next war. The development process is long, as in decades long: new weapons need to be theorized, researched, prototyped, tested, modified, re-tested, pre-serialized, field-tested (that's where the wars usually come in) re-modified, re-tested and finally actively produced. Never has a conflict seen one entire cycle, never mind several cycles of development.

The cynic would say wars are declared really just to test the shiny new weapons that were built during peace-time.

"Most weapon development is done between wars...

2009-08-30T11:32:46.331-07:00

"Most weapon development is done between wars, not in the middle of the fighting, and only desperation forces the arrival of poorly developed weapons, and they are rarely miraculous: while the atom bomb shortened the war, it did not win it, and the Me 262 did not do Germany much good either. Although the development of space weaponry might follow the progress you lay out, most of those developments will happen between conflicts, as both winners and losers will assess the effectiveness of the weapons they did field."

Most innovations developed during one war show up in the next...many times changing the way that next war is fought; take jets and missiles for example. Wars in the 50s and 60s were fought the way they were due to developements during WWII. I don't see the way space-warfare developing as any different.

Ferrell

Ian said: "All this probably wouldn't hap...

2009-08-30T10:04:12.225-07:00

Ian said: "All this probably wouldn't happen in a short conflict."

In fact I would say that very little weapon development is done during any war. World War II's uniqueness was that then end of the war saw a seeming technological leap, with the introduction of jet fighters and nuclear bombs. However, both these avenues of research had been initiated well before the beginning of the war. From theory to prototyping to pre-series to field testing to full-blown production, the life cycle of new weapon development is far longer than any war. The fact that those weapons (jet fighters and nuclear bombs) even saw action was an act of utter desperation from the sides that fielded them.

The Me 262 design was held back several times, notably when Hitler asked it be modified as a bomber, and it was finally crash-released as a fighter, mostly untested, and in the hands of pilots that were never fully trained on the new aircraft. It was only because it was released in a hurry and in too few numbers that it did not affect the war, because its superiority was apparent almost immediately. The allies, GB and the US, had jet fighters in the pipeline, but they were unwilling to throw such an untested weapon into battle. Because unlike Hitler they were not desperate, those jets only went past prototyping after the end of the war. Only the British Comet saw limited pre-series production, and never saw significant action.

The nuclear weapons released by the US were born in the same philosophy of desperation. The two bombs released on Hiroshima and the Nagasaki were completely different in theory and development, and were in no way production weapons. They were barely suitable for testing, but they were rushed to the Pacific front anyways. Hastily built, they were jury-rigged into their bombers, with the crew having a crash course in dropping methods, which mostly consisted of getting the hell out of dodge and not looking back once they dropped it.

All other "new" weapons, tanks, aircraft carriers and submarines, were merely advances on existing technologies from WW I, and had had the inter-war period to undergo rigorous testing before they were fielded.

Most weapon development is done between wars, not in the middle of the fighting, and only desperation forces the arrival of poorly developed weapons, and they are rarely miraculous: while the atom bomb shortened the war, it did not win it, and the Me 262 did not do Germany much good either. Although the development of space weaponry might follow the progress you lay out, most of those developments will happen between conflicts, as both winners and losers will assess the effectiveness of the weapons they did field.

The discussion suggests an evolution of space warf...

2009-08-30T09:39:12.521-07:00

The discussion suggests an evolution of space warfare. In the early days of the first conflict, both sides have light defences (Probably against terrorists and hijackers) and the weapons are barges set on crash courses. Someone upgrades their defences to a laser/kinetic combo that can break up and deflect an incoming barge, so the other side rigs the barge into a killer bus - Essentially a mulitstage warhead on top of a barge loaded with Rick/Ferrell's bursting charge. The best defence against that is EM warfare, setting off the bursting charge before the killer bus is in range. This forces both sides to upgrade their electronic warfare systems, and we've gone from fire barges to autonomous attack craft in a series of relatively inexpensive steps. A similar evolution could turn other fire barges into Rick's lancers, and with all that lethal hardware around you need a command craft to carry the minds (Human, AI, or GMed brain in a bucket) that make the strategic decisions.

All this probably wouldn't happen in a short conflict. The designs might be in place, but if the shooting ends by Christmas then it's hard to justify building new weapons systems. Particularly when there's all that ruined infrastructure to rebuild and treaties to work around.

Ian_M

Rick: As I recall, Anthony Jackson's figure of...

2009-08-30T09:25:53.285-07:00

Rick: As I recall, Anthony Jackson's figure of 1% drive output for beam weapons was the minimum available beam power for torch drives using inertial confinement fusion (because otherwise, you couldn't light the torch). It would not necessarily apply to, for example, antimatter initiated microfission/fusion or Z-pinch fusion, which might have much feebler beam zappers. Also, a nuclear-electric spacecraft with a 10 MW reactor could mount a laser that took its entire electrical output at maximum firepower (giving it something like a 3 MW zapper with modern laser efficiencies, perhaps somewhat better farther in the future).

Citizen Joe - True, you only have to punch through...

2009-08-29T15:45:00.175-07:00

Citizen Joe - True, you only have to punch through the cloud, not zap the whole thing. In flat space, identifying the threats is theoretically easy. But in orbital space at moderate mid-future speeds - up to dozens of km/s - trajectories are significantly curved, and picking the threats out of the clutter is tough till the last few seconds. And the last few seconds doesn't leave you much time.

A key metric in evaluating the blue/green tradeoff is seconds of unguided flight time from when laser defense cripples an incoming bus till the wreckage or fragment cloud passes the target. The unguided flight time is the interval in which you can jink, or else zap the dangerous handful of incoming frags.

If a kinetic target seeker gets within 10 seconds of you before you cripple it and force it to fragment, you'll have trouble either sidestepping or blasting through the frag crowd. If you can cripple it more than a minute out, only a jumbo kinetic, like a killer bus, poses much threat.

So, take 30 km/s as a reference speed that midfuture electric drives should be able to reach. Even small target seekers will be deadly if they can get within a few hundred km of a target before being crippled. Kinetics must be jumbo sized if defending fire cripples them at several thousand km out.

Anthony Jackson on SFConsim-l suggested a figure of merit, that the steady beam power you can put out might be on the order of 1 percent of drive engine output. Supposing gigawatt range electric drive, that give average beam power of 10 megawatts, or 600 MJ per minute, enough to burn through 12 kg of graphite.

That's not a lot of armor, so I'd say that a modest sized target seeker with an armored faceplate will be hard to stop.

With terawatt torch drives you'd expect 10 GW of zapping power, enough to burn through 12 tons of armor in a minute. But a torch missile could be coming at you at hundreds of km/s, maybe 20,000 plus km in a minute. You pretty much need X-ray lasers to stop airplane-sized torch missiles.

In the case of a laser ship vs. exploding killer b...

2009-08-29T04:41:35.950-07:00

In the case of a laser ship vs. exploding killer bus, you don't need to destroy all the fragments, you only need to destroy the fragments on an intercept course. If it is a tight cloud, you just jink out of the way. If it spreads wide, you can just punch through the middle.

Of course, if you're a ship defending other things, then you do kinda need to destroy all the fragments.

Minor quibble: if your switch is a dead man's ...

2009-08-28T23:08:30.247-07:00

Minor quibble: if your switch is a dead man's switch linked to your guidance system, what stops me from frying your electronics with a high-power laser/maser or an EMP bomb well before it's in range, thereby forcing it to detonate prematurely? You're going to need hardened electronics and a dumb-fire option in case your sensors go black. I'd probably use a dead-reckoning navigation package.

During WWII the V1 missiles had a very simple "guidance" systems. Basically you just pointed them at a target and launched them. There was a tiny impeller in the nose and inside the missile a system to count the number of rotations. The speed of the missile being known, it was just a question of maths: at the proper rotation count the missile would angle down. Not the most precise way of hitting something, but it worked well enough.

I would equip a missile with a gyroscope and accelerometer deep in the missile body. In case the guidance package gets fried, the missile would continue on its final real-time figures, accounting for range and vector, and detonate at the predicted distance. Only if severe damage is registered, risking the total loss of the bus, then blow it up, but only as a last resort, not at the point where it becomes blind.

Put damage sensors on strategic places and assembl...

2009-08-28T22:53:55.094-07:00

Put damage sensors on strategic places and assembles (nose, guidance, engines, ect)of your 'Killer Bus' and a negative signal detonator for your bursting charge. For all of you who don't know, a negative signal detonator causes the explosive to go off if it loses the signal to inhibit the detonator, once you've activated it.

Jam the control signal and it goes off; damage its vital components and it goes off; its timer reaches zero and it goes off; trip its proximity fuse and it goes off; its nav package says its in the right place and it goes off; if any one of a dozen or more sensors or circuts trips, it goes off...if none of them are triped, it will (probably) hit the target and make a rapidly expanding cloud of shrapnel. In the age of sail , fire ships were feared, and rightly so, but in the age of space warfare, 'Killer Buses' may well become the new fire ships.

Ferrell

Anonymous: High explosives work because they decom...

2009-08-28T17:45:08.763-07:00

Anonymous: High explosives work because they decompose when a sufficiently strong shock wave passes through them. This adds the energy of the decomposition to the shock, and is what gives the explosive its explosion. Since any hypervelocity impact generates a pretty serious shock wave, a kinetic round with an explosive bursting charge will naturally tend to explode when struck by a kinetic missile defense round. Pulsed lasers could also detonate an explosive charge if the beam goes through (or perhaps near enough to) the explosive, for the same reason. To have the bursting charge detonate when the missile is merely being cooked by a laser heat ray, you would need to specifically fuse it to go off once it reached medium rare.

Anon - All I know about HELRAM is a very abbreviat...

2009-08-28T17:41:55.331-07:00

Anon - All I know about HELRAM is a very abbreviated Wikipedia piece, but the situations are not quite parallel, in a couple of respects.

In atmosphere, if you zap a shell and it breaks up, its aerodynamics are drastically altered, and the fragments will end up nowhere near the target the intact shell was aimed at. In space you just get a fragment cloud spreading out along its previous track - which is exactly what I want for a fragmentation kinetic.

And I picture most fragmentation kinetics as being (when intact) considerably bigger than artillery shells, and likewise much bigger than the spot size of the lasers zapping them. The defender's zaps are aimed to cripple it by knocking out key components, especially the main guidance logic and deflect motors.

The destruct circuits only need to be armed well after launch, and once armed they detect such crippling damage and send the destruct signal. (The destruct system can be networked so that no one zap knocks it out.)

Explosives are dangerous stuff, but there's no reason the destruct system would be so sensitive that it goes off if a maintenance tech looks at it funny. In fact the safety factors should be not unlike the destruct explosives used in present day space boosters if they stray off course during launch.

Really, for a rocket artillery to bypass an active...

2009-08-28T16:33:40.789-07:00

Really, for a rocket artillery to bypass an active defense system, you'd need a design so that the default was for it to explode. Tamper with it in any way, and boom goes the dynamite, the exact opposite of what you wanted to happen. Setting aside the orifice puckering that idea generates in me as one who would be working with such a munition (it could make the Forrestal look like a relaxing drill), it is rather hard to come up with such a design. The only thing that springs to mind is antimatter, and if I have a readily available supply of it I can think of many things far more useful to do with it then shoot people.

Your scenario in which this bypasses laser defense...

2009-08-28T16:25:54.870-07:00

Your scenario in which this bypasses laser defenses assumes that the laser destroys the bus, but that the bus then explodes as it was meant to. It is essentially based on the prediction that a defensive system designed to make the charges explode off target fails to make the charges explode of target. Well yes, if I have a system that does nothing to protect me it isn't going to protect me. But give the iron mongers their due, they are smarter than that. We've had HELRAM since 2004, and that is the exact kind of system needed here.

Your system is essentially moving artillery guns into space (yes, missile buses have an analogue in rocket artillery). Problem is that we've been working against that kind of design for quite some time. While cluster munitions may not pack as much of a punch as your 10 kg fragments, humans are much less resilient than a space cruiser. Once you adjust for scale, I see no reason to assume that the counters we are developing to protect soft and squishy infantry will be insufficient to protect an armed and armored space cruiser.

What Jean said. I conceived the killer bus as a we...

2009-08-28T09:34:33.649-07:00

What Jean said. I conceived the killer bus as a weapon primarily against big laser-armed 'battle stars,' thus in a tactical role. If you use it against, say, a spacecraft construction cageworks (i.e. 'shipyard'), then you're using it in a strategic role. But against undefended targets you don't need anything as even as semi-sophisticated as a killer bus - just release a cargo pod filled with scrap on a collision course.

In orbital combat, large scale use of kinetics could render orbits unusable - not necessarily from the kinetics themselves, if they are traveling above escape velocity, but from the wreckage of smashed targets.

I only start getting fuzzy at about 1 am... oops l...

2009-08-27T22:29:36.142-07:00

I only start getting fuzzy at about 1 am... oops look at the time.

Jean, a fine point of distinction! Thank-you, it&#...

2009-08-27T22:26:32.107-07:00

Jean, a fine point of distinction! Thank-you, it's late and my thinking is starting to get fuzzy (my wife would say that was my normal state...); well, I'm off to bed so I'll talk to you later...I enjoy your comments and ideas; you've obviously have thought them through with great care!

Ferrell

Um... any weapon deployed on a battlefield would b...

2009-08-27T22:20:20.687-07:00

Um... any weapon deployed on a battlefield would by definition be a tactical weapon no matter how important it is to the fleet. A strategic asset is one that matters over the course of a campaign, such as the shipyard that built it.

If you deploy a nuclear weapon on a battlefield it's a tactical weapon. If you use one to bomb a city behind enemy lines it's a strategic weapon.

The bus could be used in a strategic manner if it is targeted at a planet or a station, or even to interdict a shipping line by seeding it with navigational hazards. If it is used in battle against an attacking ship, it's definitely a tactical use.

The ship that is the target of your 'Killer Bu...

2009-08-27T22:13:26.310-07:00

The ship that is the target of your 'Killer Bus' seems to be a strategic asset, so to take it out would seem to be a strategic response. The weapon itself doesn't have to be a strategic one, just the purpose behind its use. And if you use one in the orbit of an enemy planet (Mars or Titan, for example), then it also becomes a strategic weapon. One 'Killer Bus' is a tactical weapon; use a hundred and it becomes a strategic one...

Ferrell

I don't really see the bus, even the big one, ...

2009-08-27T22:02:37.107-07:00

I don't really see the bus, even the big one, as a strategic weapon either. The explosion will spread the debris out far too fast to have any lasting effect beyond the day's battle. At worst they'll present a small hazard to navigation, but it would be a decidedly unlucky ship to randomly hit a one centimeter object in the whole lot of nothingness of space. It doesn't sound like the kind of weapon you want to use in orbit either, unless you know you're losing, and as part of a scorched-earth gambit.

I intended the killer bus as a 'tactical' ...

2009-08-27T21:56:15.807-07:00

I intended the killer bus as a 'tactical' weapon, since even though grotesquely big its intended target is major combat spacecraft. In the 17th century, fireships were a regular part of fleets and even sometimes purpose built, so that's at least one precedent for very large expendable weapons!

Smaller versions could be any variation on what you describe, but note that in principle you need no 'warhead' other than the bursting charge - the structure, engines, fuel tankage, guidance computer, etc., all become part of the fragment cloud. Nothing is wasted, so to speak.

I suspect that a Claymore mine would be too late in the game to be very useful, but ordinary bullets fired toward an incoming kinetic might shatter it several km away, far enough that most of the sub-fragments will miss you.

I like the claymore strapped to the hull idea. It ...

2009-08-27T21:50:12.261-07:00

I like the claymore strapped to the hull idea. It seems similar in concept to "reactive armor" which are basically just that and meant to counteract the incoming explosive jet created upon impact by a prenetrator to rob it of momentum. I don't know how effective it will be as a purely point-defense weapon because of the low probability of randomly scattered shrapnel to actually intercept the incoming ones at range, but perhaps as a last ditch resort when the normal CIWS's no longer have the time to intercept them or are already overwhelmed.