# Discouraging missile alpha strikes

I am looking at tactics for using missiles as space-to-space weapons. The missiles in question will be chemically fueled, higher acceleration but lower deltaV than the warships.

Since they are essentially self contained, you can chuck your entire missile load out out a hatch, and fire them in one massive salvo.

Against a single target this seems always like the ideal strategy. Laser/Particle Beam/Gun point defense is all limited by energy throughput, making it essential to minimize the time PD has to engage the salvo. Since active defenses are not degraded, saving missiles makes no sense. If your wave did not get through, neither will any equal sized follow-up.

Edit: Heat may degrade active defenses, but if you fire the second salvo along with the first one, you have a much better chance of getting them through than allowing engagement time.

What device or method could be used to draw out missile combat and make multiple waves a desirable tactic?

• Although you posit that "active defenses are not degraded", that is not necessarily the case. Any active defense will generate heat, and the amount of heat that can be radiated over the course of a single engagement will probably be low. Therefore, missile defenses will use up heat-sinks, although this doesn't really mean that staggered salvos will be better than a single massive salvo. – Gryphon Feb 19 at 18:36
• You may have backed yourself into a corner here with the constraints. If defense systems aren't degraded by attacks, then you're right that there's no reason to do any attack other than what is most likely to overwhelm the defenses and destroy the target in one strike. Any attack that doesn't get through the defenses is a waste, so one big attack makes sense. Perhaps if a smaller attack with only a few missiles had some non-zero chance of success, it might make sense to try that attack repeatedly to keep rolling the dice. – Jared K Feb 19 at 18:48
• also, where do the missiles come from? i only ask because you wouldn't want to launch everything in one go obliterate the enemy ship and then turn around and find another ship and have nothing left. so surely making resupply a significant factor in the battles would mean conserving ammo is important which in turn would remove the usefulness of a massive alpha strike – Blade Wraith Feb 19 at 18:59
• Of course you may retain a reserve against additional targets. You still want to throw a large salvo against the first ship that you expect will kill it in one go. – Whitecold Feb 19 at 19:07
• @Whitecold I believe you meant "higher acceleration but lower specific impulse" in the first line of the OP. Specific impulse is a measure of the efficiency of a rocket- the delta-V it would produce per kilogram of fuel consumed if you ignore the mass of everything but the fuel and the fact that burning fuel changes your mass. Notably, chemical rockets do indeed tend to have high thrust but low specific impulse- they can accelerate quickly, but run out of fuel just as fast. If your warships have ion/plasma thrusters with high specific impulse but lower acceleration, your premise makes sense. – Someone Else 37 Feb 20 at 2:29

## Short-Term but High Effect Shield

Introduce a shielding capability that is extremely effective but has a short duration and long cool-down. Maybe a ship can run it in 5 second increments, store up to 30 seconds worth of shield, and needs to restock or take a huge amount of time to replenish the reserve.

This essentially gives it the ability to absorb the 6 largest salvos sent against it. IF you only send a few huge waves, they will all be blocked by the shield. If you keep up a steady bombardment or many smaller waves, the shield becomes much less effective.

There should be numerous physical/handwavium ways to create a shield like this.

• If you don't want shielding, you can get the same effect by being able to run your point-defense in "burst mode": greatly-increased output, at the cost of a cooldown period afterwards. – Mark Feb 20 at 21:28
• You can never be certain that what is currently just one target will stay just one target. Each side would be wary of being tricked of flushing all of their missiles against a part of the enemy force.
• Missile seekers might observe the defensive EW of the target and transmit this data to the follow-up salvo, increasing the hit probability. This is balanced by adjustments in the EW.
• It could be easier to temporarily degrade the defenses of a target than it is to kill it outright. For instance, a near miss might blind the sensors of the target. So the 'main wave' of the attack could be preceded by a few 'defense suppression' missiles. (Since the 'main wave' knows the timing, it can cover or avert the seekers to protect them. Blinding countermissiles would still be a problem.)
• In a similar vein, the 'main wave' could be followed by a few missiles to 'clean up' cripples before the damage control teams can get them back into battle. Mixing them into the main wave could mean that these missiles are wasted against an intact point defense.
• Missiles could work better if they are guided for most of the flight. This requires sensors, computers, operators, and communications on the launching vessel. These could be in short supply.
• I really like the EW suggestion, but I am not sure how to model it best. There should be some over-time component, but also number of sensors observing. – Whitecold Feb 19 at 20:31
• I built an entire ‘world’ (two battleships over Io) based on missile/drones fighting each other for juuust enough local supremacy to hit the other guy. Electronic warfare was a big part of it, and all the drones were tiny little learning machines that the ‘gunners’ tuned over the course of the battle, but for the most part relied on observing the destruction of their comrades as a means to eventually employing the winning tactic. Long story short both ships blew up. – Joe Bloggs Feb 19 at 21:26
• @Whitecold, assume that each missile is decoyed with a probability of x%. This probability can be reduced if the missile has current data on the target EW, and it can be increased if the target EW has current data on the missile(s). You can launch multiple missiles with different seeker settings, but the target has only one setting at a time -> staggered salvos force the target to "show their hand." – o.m. Feb 20 at 5:10
• Launching everything in one batch also means, that the missiles travel close to each other. If one explodes, it could damage the others. One might want to leave space/time between missiles. Either send everything once, but from different directions, or leave time for the debris to leave the zone. – G. B. Feb 20 at 8:39
• +1 for the first point alone - especially if the observed target may be a decoy – KerrAvon2055 Feb 20 at 9:56

Answer inspired by "The Matrix Revolutions"

One of the effective anti-missile weapons is an EMP charge. Once an incoming wave is detected, a powerful missile carrying an EMP device is launched. Once in proximity to the wave, the missile is detonated, making the entire wave ineffective. The EMP charges, however, are large missiles and are unlikely to be deployed against individual attacking missiles or small salvos.

• Yes, whatever the mechanism, any defense which can affect an entire salvo regardless of size (but which has some other limits) would tend to argue against firing all missiles in one salvo. – Dronz Feb 20 at 0:02
• EMPs tend to only affect electronics. If I was either of the warring parties, I'd look into ways to make my missiles function without any electronics in the rockets themselves. that might actually be a good question. – Nzall Feb 20 at 14:19
• @Nzall It may be worth noting that a similar mechanism could be employed if we're targeting missiles: for examples, a condensed cloud of metal balls that would trigger the missiles. – Nathan Feb 20 at 16:19
• EMPs can be shielded against by hardening the wiring. One would presume that a society in space regularly and long enough to have a need for space warfare would have experience in shielding. – Keith Morrison Feb 20 at 19:08

Decoys and electronic warfare.

You've been tracking that battleship as it closed to engagement range (yes, you have engagement ranges in space. Fire your missiles from too far out, your enemy lets them burn then zigs out of the way.) You fire off 100 missiles and your target release a dozen decoys. Decoys don't have the resources to pretend to be a battleship for too long and they are trivial to kill. Your missiles split up, each target has about 8 missiles going for it. Your 100 missile salvo is degraded to 8.

What you have to do is fire some missiles and see what happens, followup birds have their targeting adjusted based on what the first birds learned.

There's also the issue that if you fire too dense a group of missiles that the enemy will fire a missile at your missiles. Even a nuke doesn't have much punch at any distance in space but all you need is a mission-kill and frying their seeker does that. So long as you can avoid running into a fried missile it's harmless.

A dense group of missiles also causes communications issues--you're trying to punch a signal through all that exhaust which will contain some very energetic chemicals.

• Similar to the beginning of "Red Storm Rising" by Tom Clancy. Incoming decoys looked like actual bombers. When the decoys were taken out the bombers were able to attack before the defensive fighters could re-arm. – MongoTheGeek Feb 20 at 18:56
• @MongoTheGeek Exactly. That's what can happen when you dump all your ordinance against decoys. – Loren Pechtel Feb 22 at 20:56

Here are a few possible answers that come to mind:

Sure lasers can't punch through the armor of the enemy ship, but if the enemy was to deploy a large missile loadout out one of their hatches, the laser could destroy that. In addition to instantly wiping out most of the enemy ship's missiles, the explosion created by shooting the loadout would heavily damage the ship itself. That is why the ships would choose to deploy smaller loadouts one at a time- if a laser shot the loadout, the explosion would be smaller and the ship would still have missiles to use.

Maybe the ships are fighting near an object that neither of them want to destroy. It could be a planet, or a field of explosives (space mines) that will explode in a chain reaction if hit. If any of the missiles miss their target and hit the object, something bad will happen. If both sides want the planet intact or both have ships within the minefield, they will use precision strikes instead of carpeting the enemy with missiles.

@o.m. brought up the idea of sensor interference messing with targeting. Building on that, having large salvos of rockets fire at once blinds sensors, resulting in a lot of wasted missiles that miss their target. The rocket engines on the missiles and the flashes of light missiles create when they explode could both interfere with sensors.

The shielding on the ships might be thick enough to sustain several blasts from rockets. If the ship has a limited number of rockets, they will focus on one spot on the enemy ship to try and punch through the armor. Salvos would be single shots with a few seconds in between, with all of the shots focused on a single spot on the enemy ship.

As @G0BLiN suggested, missiles themselves are limited. Launching large salvos is wasteful if a few missiles might take out an enemy ship. Ships would deploy only a few missiles at once, then wait for the explosion to clear before determining whether to fire again.

Unlike on Earth, where reinforcements are nearby, reinforcements in space are far away. They need to be out of the line of fire- behind an asteroid or planet where the enemy can't shoot them. Missile or ship resupplies might take hours or days, so rationing of missiles is a must.

• Another reason: missiles are a limited resource - unlike energy based weapons (lasers, plasma torpedoes etc.) which can be used indefinitely (typically have cool-down / recharge time but as long as the ship's power plant works, they can fire). Missiles, on the other hand, take time and effort to manufacture - even if the process can be done on-board (probably possible for the larger ships) - there's a limit to how many you can carry (they have mass and take space, these are limited resources for a combat space vessel). If 5 missiles are likely to do the job, you don't launch 500 at the target. – G0BLiN Feb 20 at 12:55
• @G0BLiN True. The OP pointed out in the question that energy weapons were unfeasible, which I assumed was because of a ship's shielding. I tried to find a way that lasers could be used while still having missiles be the main mode of combat. – John Locke Feb 20 at 14:24
• just suggesting another reason not to use an alpha strike, maybe a more concise phrasing would've been simply "missiles are too expensive to waste, and alpha strikes are very wasteful". I like your idea that deploying a large loadout is risky for the attacker, encouraging smaller salvos. – G0BLiN Feb 20 at 15:03
• @G0BLiN Thanks, I will add that to the answer – John Locke Feb 20 at 15:04

## Fratricide

Chronicidal and Alexander's answers combine to be the winner.

In the back and forth of nuclear war, one thing the US tried was the tight-pack. Earlier, they had tried spreading silos far apart, forcing the enemy to counter with 1 missile per silo, which the enemy promptly did, set up to arrive time-on-target, or all together to overwhelm any ABM systems.

So the US threw the "Time on Target" strategy right back in their face. With the tight-pack, the US put them close together - hardened enough that all but the direct-hit target would survive. But close enough, that a time-on-target attack would ensure that the first missile would cause fratricide -- all the subsequent missiles would slam into the shockwave of the first missile, and be damaged sufficiently to not detonate.

So in your case, it wouldn't be shockwave, it would be something like shrapnel - suppose you had interceptor missiles of roughly equal warhead velocity x mass to the attacking missiles, so their collision would cancel each other's velocity before causing a massive explosion of sharpnel to occur relatively stationary in space. This creates a localized Kessler Syndrome between attacker and defender, then causing fratricide of a salvo of any size -- the bigger the salvo, the bigger the Kessler Syndrome.

The ship would stock two kinds of interceptors.

• small, designed to break an incoming missile so its attack would be ineffective, but it would do little to change the velocity vector of the incoming missile and its soon to be shrapnel bits; those would continue on past the defender at roughly equivalent speed, and be dealt with by the defender's normal micrometeorite shield. These were numerous but its launch rails or targeting could be overwhelmed by a salvo. So... they also have
• Large, designed to match the mass x velocity of an attacking missile, and create this "Kessler syndrome" field of debris. These missiles are more precious, and would be reserved for salvos large enough to overwhelm the first defense.

As such, attackers find that the most effective attack is a "happy medium" - too small a salvo to justify trotting out the Kessler defense weapon, yet large enough to get a couple past the single defenses if you get lucky. So you have numbers of such salvos until you get lucky.

See also Hellfire vs Arena. Too small a salvo (1) is efficiently dealt with by the Arena defense system. Too big a salvo, well, it would certainly squish the tank, but would be totally unmanageable from the attacker's end, and would run you out of ammo, leaving you unable to attack other tanks. Generally it's a lose if the ammo you throw at the tank costs more than the tank.

Space is big. So, solutions that rely on area effect weapons or fratricide probably won't work. The attacker would want the missiles to spread out anyway. This allows the missile swarm to get some of the missiles to the target even through debris and extreme maneuvering of the target.

If you aren't looking for a super science answer like a limited time shield (stops everything for x amount of time from, for example: Macross), then look at the "wild weasel" (WW) electronic decoy from Star Fleet Battles. A similar tech was used in the Honor Harrington novels. If every large ship has one or more of these, they can divert all or the majority of a single wave of missiles.

In that case, the missile cruiser would either want to plink away with small groups to avoid the deployment of the WW or fire groups just big enough that they need to deploy the WW and hope that you have more groups than they do WWs.

Anti missile swarms. Small missiles that target incoming missiles. If it takes 2 anti missiles to take out a missile but the anti missiles are 1/4 the size of the attacking missile, you can wipe the alpha strike and till have room for offensive weapons. This works even better with fleet antimissile ships.

Layered missile defense would work too. Anti missiles, lasers and short range gatling guns. Thin them out in each band. If multiple ships can coordinate, they can block for everyone.

The best case for solving the problem is to not make the missile swarm the best or the worst but come up with rock-paper-scissors strategies.

# Guided Point Defense

Point defense can, in theory be very effective in space. Given the speed at which objects are traveling, it doesn't really make sense to include a "warhead" on a missile to be honest. The missile IS the warhead, since a collision at several thousand meters per second will likely destroy the enemy ship on it's own. The only reason to make it a missile is to give it extra speed for said collision, and to re-direct itself to keep the enemy from dodging.

Using this same logic, you could conceive of a point defense system that essentially acts like a smaller version of the above. It would simply be small bullets with cold gas thrusters on the sides for maneuvering. These would then attempt to collide with the incoming missile.

A collision at those speeds would disable the missile's guidance systems. It would still be hurtling towards your ship at speeds great enough to vaporize you if it hit, but without guidance a simple maneuver would allow your ship to dodge out of the way.

You're firing unstable high-yield devices

The missiles are sort-of stable when in storage, but as soon as the rocket engine starts firing, the thing heats up, which primes the explosive. When hot, a tiny nudge will cause them to explode, detonating any other missiles near it.

These things are so high-yield that they don't even need to hit the ship, they just need to get near it. If you fire a big salvo, at maximum you have a single near-hit since the defenses take out one, and a huge shockwave from the resulting explosion makes the other missiles obsolete.

The missiles are on erratic courses to avoid being hit by defenses, but throwing out a bunch at a time increases the chance one missile will get hit, and one is enough to ruin an entire salvo. As a result, a usual attack is one missile at a time. Launching many missiles is only done in utter desperation up close, and will likely obliterate both ships.

Missiles explode. If you launch them all as a single dense cluster salvo, then my Point Defense only needs to detonate 1 of your missiles to trigger a chain reaction. If you spread them out to prevent that, then you are either launching a bombardment of continuous waves, or launching less missiles.

Of course, by dropping missiles as you travel, you can also increase your angle of attack - but that takes time, and your target can move.

• I would not be worried about chain reactions. Nukes don't spontaneously explode, and the fuel on kinetic missiles not powerful enough to cause a chain reaction. – Whitecold Feb 20 at 14:54
• @Whitecold on the other hand, detonating a counter-missile in the middle of the salvo-formation would wreck the bulk of the incoming ordnance and render them relatively harmless. – Ruadhan Feb 20 at 16:29

If you desire multiple missile volleys to be the standard, then you need to have some active degradation of the defensive systems. This could be achieved by having specific payloads in your primary volley that cause this degradation. Any active defense requires high speed, high precision sensors. They need to be looking in every direction, all the time, across a number of RF bands.

So sending all of your highest yield at once against the enemy isn't as likely to produce results against a pristine sensor array. Sending an initial wave to obscure, overwhelm, damage, or destroy those sensors will then let your killshots get through.

So lets say you launch 100 missiles at once, with 10% of them designed to locate enemy sensor arrays and relay that info to the rest. Another 10% of them are designed to target those sensors with a dense, shot gun like blast of small inert projectiles. Another 10% are designed to intentionally fracture into millions of pieces to overwhelm radars. Another 10% have their own laser systems integrated and try to fry the sensors/ point defenses from range. The remaining missiles could have smaller payloads or just be inert decoys.

The point is that after a primary volley, the enemies sensors and point defenses have been partially damaged. This process can be repeated until they are blind or helpless enough to finish them off as you please. This approach will be expensive, but hopefully less so that using your rarest, heaviest, most expensive weapons in a single massive assault that could very easily be overkill, or could also leave you a sitting duck.

One fairly obvious solution:

Kessler Syndrome is undesired.

Explosions in orbit can render a planet unable to attempt space travel. If it's groups fighting over territory, you'd need to make sure that each volley doesn't cause a chain reaction. In a stable orbit, this could mean generations waiting for debris to fall. However, ships in approach and not in a standard orbit may expect most of the material to fall into decay and burn up IF it stays inside an appropriate window (still very risky).

In other words, if they blow up too much too fast, they blow up everything, and nobody wants that.

It's the same reason most current militaries build weapons more about efficiency than raw power. It's easy to build a weapon that will wipe your opponent off the face of the planet at the push of a button. It's hard to design one that will do that AND leave you in one piece too.

Edit: Additional notes In general, due to a lack of friction to slow down the shrapnel, missiles in space are a bad idea overall, and are just as like to destroy the ship firing the missiles as the ship hit. Equal and opposite reactions with a friction-less environment mean there's a good chance shrapnel from the missile will go flying back towards the ship that fired, shredding it. Not only does this apply to missiles, this applies to ALL explosive and projectile weapons. In space, the best weapons will be capture weapons and weapons for close combat, and shrapnel-less energy weapons like gamma bursts and EMPs and microwave weapons.

The firing ship can only control so many

Missiles go fast. This causes some Doppler shift in... Most things. So, the launching ship is in control of the missiles from launch to hit. Bigger, better sensors and bigger, better computers. While the missiles have some on board targeting systems and computers (In case of effective jamming), the ships are better.

But a ship can only effectively target, track, update, and communicate with so many missiles. So while they could fire everything, it's less effective.

Similarly, fewer missiles means if the enemy can coopt the command and control mechanisms, fewer missiles are lost. Each salvo would have different, generated encryption keys, so while the enemy might manage to divert one salvo (Highly unlikely that there would be enough delta-v to get back to the launching ship), it'll be more difficult to do so for the second one since they have to start back at square one. If they are launched in one wave, they all have the same keys and can potentially all be messed with.

• The ship doesn't really need to control the missiles. An infrared seeker makes them fire and forget, and even with semi-active lidar one target illuminator can control unlimited missiles. The only missiles that I see possibly fully command guided would be countermissiles, as you want those as tiny as possible. – Whitecold Feb 19 at 20:24
• What does the Doppler shift have to do with it? Can't that be corrected for? – John Locke Feb 19 at 23:05
• I should point out that this solution(limited control links) is the reason used for multiple missile salvos in David Webbers Honor Harrington series. Given how popular that one is, I'd say steal from the best. – Eugene Feb 19 at 23:14
• @Whitecold In the real world missile seekers are much shorter ranged than the sensors of the system that fired the missile. – Loren Pechtel Feb 20 at 16:45
• @Loren Pechtel I'm planning to have the whole slew of guidance systems, passive, semi active, active and command guidance. Inertial guidance and IR sensor should work quite well against most targets, especially when radiating a few GW of waste heat. A ship mounted telescope won't improve too much, since with the additional range the target may simply run the missiles out of fuel. – Whitecold Feb 20 at 21:00

One "solution" to your question would be missile launchers that impart a significant velocity to the missile in the "launch" sequence - if I remember correctly Tomahawk missiles have very low velocity upon launch i.e. when exiting the launch canister - while rocket-assisted artillery rounds have a lot of velocity at the start.
The "explanation" for this feature (forced launch) would be that the missiles accelerate slowly at low speed, so launch at high speed lowers (by a lot) their time-to-target (also, "fuel" used for early start acceleration can't be used later for maneuvers).
On reverse, the missile launchers are limited in energy used per minute either by cooling issues, or by energy generation issues.
These being said, the "large EMP defense" mentioned above is a very valid answer.

Another possible answer would be that the total surface of the ship is limited (for real or handwavium reasons) so it simply doesn't have the surface area to launch everything in one go.
Yet another possible answer would be that the missiles can only survive behind a lot of plating, and creating a lot of tunnels through that plating makes the armor too weak (this you could "support" with stories of battleships lost by "lasers through the missile tubes" phenomenons).
And yet another possible answer would be to have shields that can only have very small and temporary "holes" - if you try to open "windows" for a full salvo, the entire shield will fail - and even a small hole opened more than a couple of seconds will propagate outwardly and lead to instabilities.

Well, plenty of ways for a technologically oriented party in a war to introduce "overpowered" technologies and win against a brutal opponent...

No one answered with current doctrine?

You dont send a destroyer across the atlantic to unload it's entire missile rack on a single target. It's expensive overkill and leaves you vulnerable to future attack while you try to make it back to port for a reload. Especially when the defender can signal others to your location, and those others could attempt to catch you as you try to flee.

Another option: most of the missiles will likely be kinetic, meant to slam into the space ship and tear through. This means they cant be detonated easily and destruction of the missile means the debris will still be able to tear through you. Solution? If the enemy sends a single giant wave, you can predict their course and put a big bomb in their way a distance away from you. This bomb will disable the guidingsystems of the missiles (if not destroy them) and blow the debris and damaged missiles off-course from your ship. At the very least it'll reduce the total damage received.

• But the destroyer will absolutely attempt to kill the target in the first volley, because if you fail, you will likely be dead. As far as bombs go, even high yield nukes fall off very quickly. 1/r^2 plays no favor, and missiles will likely have some ablative armor against lasers, that should work against xrays as well. The only time the missiles need to be close to each other is during terminal guidance, otherwise you can space them by kilometers – Whitecold Feb 21 at 18:22
• @Whitecold Ofcourse the destroyer will absolutely attempt to kill the target! But not at the cost of being defenseless afterwards! You don't fire a bunch of missiles knowing it's not enough, you fire enough so that the target is disabled or destroyed and then see if it needs more, rather than waste your precious ammo and be left out in the cold once more enemies show up. – Demigan Feb 21 at 18:54

The missiles have Fission devices as their warheads

In addition to fireball and debris cloud effects, fission weapons have a unique problem: chain fizzling. When a nuclear fission weapon detonates, the chain reaction inside it's core generates a large number of high energy neutrons, such a high neutron flux will cause fission reactions in nearby cores , even if they are subcritical.

The result of such fission reactions is that, due to the large amount of heat generated by the secondary reactions, the internal components of any fission weapon would experience thermal shocking and decomposition, which would disrupt the precise geometry that is needed for implosion type weapons to properly implode and assembling a critical mass.

Essentially, one detonated fission device causes other devices nearby to deactivate, therefore, the missiles have to be spaced separately enough from each other, which would stretch a salvo into a more continuous flow, instead of a short burst.

Also, the enemy can employ a neutron bomb based point defense system, by launching a neutron generating device on a missile into the enemy salvo and detonating the device inside the swarm, one shot of a slightly larger missile can easily disable an entire salvo. Since neutron bombs or other area effect weapons in space would be quite large and heavy, they will be also slow reloading and one ship won't have too many of such devices. Therefore it will be much more wiser to spread out the shots instead of clustering them, and hope that the enemy will not be able to take out the entire salvo within one or two reloaded they have before some of the missiles reaches target.