Can ICBMs be given stealth like planes?

[Chaotic Neutral]

Is it possible to stealth an ICBM like a B-2 or F-22, or is it just too big?

Just wondering.

[Chardok]

ICBMs, IIRC, travel so fast and high that the need for stealth is trivial. given the current state of ABM technology (PATRIOT notwithstanding) It's going to be a long time before we need to equip them any sort of technology approching the level on the B-2 or F-22.

[Chaotic Neutral]

But then how are their launches detected? Or are they not?

[Mr Bean]

But then how are their launches detected? Or are they not?

Heat bloom of the rocket engine kicking in. Unless you intend to fire them via Mass drivers steath and ICBM belong in the same sentence as much as "non-lethal flamethrower"

[Chaotic Neutral]

I was going to say that...

So why don't we have those? The ability to nuke someone before they know what happens seems useful.

[Metahive]

The ability to nuke someone before they know what happens seems useful.

Useful for anything that isn't of dubious morality? What situation could there be were you absolutely need to launch a nuke at someone without anyone noticing that doesn't involve an act Bond Villainy?

[Phantasee]

The only purpose in starting a nuclear war by stealth is so nobody can blame you for it when humanity starts recording history again on glow-in-the-dark animal skins.

Also, how many mass drivers have you seen anyone using to launch anything? This may be a key factor in using rockets over a technology that is still under development.

[Chaotic Neutral]

If the idea is sound, why hasn't the government thrown large sums of money at it?

[General Zod]

If the idea is sound, why hasn't the government thrown large sums of money at it?

Because there are ways of identifying a nuke's point of origin after the fact. Unless you plan to obliterate the country into oblivion they'll know who hit them shortly afterword. If you do plan to obliterate them into oblivion why bother with stealth?

[Stuart]

Is it possible to stealth an ICBM like a B-2 or F-22, or is it just too big? Just wondering.

Basically no. It's been given a lot of thought over the years but the problems are simply insuperable. Things like radar absorbant materials weigh too much and are ineffective given the environment. The kinds of shaping technology that reduces radar cross section are incompatible with making a missile that works. Jammers can mask the return signal but track-on-jam (and home-on-jam) are well-understood technologies. There's no way the heat signature of a missile can be masked. So, no, a stealthy missile is an impossibility.

Chardok is utterly wrong though; missiles are very vulnerable to ABM defenses. They always have been, we've been able to hit them on a routine basis for fifty years now. Any kind of investment would be much better invested in trying to work out a practical way of making the things maneuver. At the moment, that can't be done either.

[Korto]

Well, Stuart's pronounced it impossible, and I'm pretty damn willing to take his word for it, but let's for hypothetical's sake imagine it could be done. The missile could be stealthed, and launched by means of a mass driver (which would seem to make it more of an inter-continental guided artillery shell, but whatever). This enables you to launch a massive nuclear strike, and the first anyone knows about it is when a country is erased from the map.

How big would these mass drivers have to be? How many for the needed first-strike? Would it be possible to build them without anyone knowing? I would think not. So everyone knows the capability you're giving yourself. Not even your allies are going to be at all happy about this, and as for your enemies? Can they afford to sit back and let you build this, or are they going to be forced to act first?

Congratulations. You just started World War III.

[adam_grif]

ICBM's not so much, but cruise missiles and the like can be stealthed. The AGM-129 comes to mind, although I'm not sure if it's stealthy to the same degree as a B2.

[Sarevok]

The JASSM is supposed to be stealthed to allow it to go through air defenses a normal cruise missile cant.

[Vehrec]

Forget the missile itself, what about the Reentry vehicle that actually delivers the nuke? That's unpowered, would stealthing it to penetrate local defenses be practical or desirable?

[someone_else]

You can stealth three things in a ICBM:

-The booster, and that's generally useless since its rocket engine gives are rather BIG signature for all the time. The same for each stage.

-the orbital tug that maneuvers to aim the indivitual reentry pods, and remains useless since its maneuver jets can be spotted easily anyway

-The reentry pod with the warhead, and that's generally useless since anything reentring will have a plasma sheath that will reflect radio waves pretty well on its own (the reson why you can't use radio to chat with Ground Control while reentring), and probably show well on IR scanners too.

The main defence of reentry pods is size and speed. They are more or less human-sized and hitting a human-sized target travelling at such speeds isn't a joke.

As a general rule of thumb, anything with a rocket engine cannot really be stealthied effectively.

Cruise missiles tend to use air-breathing engines, thus are more or less kamikaze aircraft and can be stealthied just fine.

[Sea Skimmer]

Forget the missile itself, what about the Reentry vehicle that actually delivers the nuke? That's unpowered, would stealthing it to penetrate local defenses be practical or desirable?

The weight would be a killer and nothing can change the RV being much hotter then the background, which is space and thus rather cool. All the current US ABM missiles are based on infrared guidance, and work is being done on space based infrared sensors which can track warheads in space. Infrared can beat a lot of stealth planes and missiles too, but something like a stealth cruise missile can fly low and exploit terrain clutter and weather to help hide it from the infrared sensors. None of this is possible for an ICBM warhead in a vacuum.

-The reentry pod with the warhead, and that's generally useless since anything reentring will have a plasma sheath that will reflect radio waves pretty well on its own (the reson why you can't use radio to chat with Ground Control while reentring), and probably show well on IR scanners too.

Not all radar is affected by the plasma sheath equally, UHF bands are quite effective at penetrating it which is why almost all strategic early warning radars are in the UHF band. Enough raw power also works, and well, the plasma only affects a specific part of the reentry phase anyway. So in general its a problem that can be worked around for ABM defenses. Its more problematic to broadcast a radio signal from the reentry object because such objects even the shuttle are fairly small and don’t have massive levels of power or huge antennas to work with

[Stravo]

I assume that what you want to do is cut reaction time. Launch to a point where the other side has little or no time to react, hence one of the advantages of ICBM subs and a big part of the reason we were really concerned about some missiles 90 miles off our coast during the Cuban missile crisis. If you can find away to set up a nuclear launch platform in low orbit you can launch a few missiles right down at your target and cut out the travel time from Russia (or wherever they are coming from) to their targets here in North America. What sort of travel time are we looking at in the instance of a low orbital launch if say the platform is actually passing over the target?

I'm sure in the end ballistic missile subs are still cheaper and a more reliable method than a Bond villain stealth platfrom in sppppaaacceeee.

[Skgoa]

You can't launch something "straight down" unless you have ungodly amounts of ability to generate velocity. (A railgun or something like that...) What you would do is release the reentry vehicle and slow it down so that it gradually falls down to earth. Thats going to be a relatively slow process[1] (compared to the flight time of an ICBM) from any kind of reasonable orbit. I.e. not one where the amount of unbound oxigen atoms makes your KillSat rust away within years or makes you spend to much fuel to just stay up there, due to atmospheric drag.
Personally, I would go for stealth cruise missiles launched from drone subs right of the coast. But afaik the technology isn't there, yet.


[1] That means there actually is a considerable warning period, if you already have ABM and space tracking capability. Even if its just a simple meassurement of the KillSat's weight - wich you can't hide in space - and comparison to what would be expected. Since the launch platform must by definition orbit faster, it will fly over the target sooner and will ALWAYS spill the beans, even if the reentry vehicle was still over the horizon. And its not going to take long after the launch of your first KillSat that everyone who can afford it starts tracking them.

[Colonel Olrik]

Chardok is utterly wrong though; missiles are very vulnerable to ABM defenses. They always have been, we've been able to hit them on a routine basis for fifty years now. Any kind of investment would be much better invested in trying to work out a practical way of making the things maneuver. At the moment, that can't be done either.

Fin actuation systems at high operating temperature and speeds are very complex for a relatively small structure. I've heard proposals to add side thrust rocket modules, if you use a gel propellant integrated in the missile's body then you get an easy to control lateral maneuverability without the stability and storage problems of using a liquid propellant for this function.

[Sarevok]

I seem to recall reading that hypersonic gliders may present another solution to the problem. Would it be possible to use them as a maneuvering and difficult to intercept reentry vehicles ?

[Colonel Olrik]

An hypersonic glider is not a missile so you're talking about completely different things. Your glider has to be taken to the operational speed somehow and it has to be complex and made of quite exotic materials if you want range. We don't reach hypersonic now with missiles, only with flight demonstrators scramjets and real operational models are at least a decade away.

[Sea Skimmer]

A long range ballistic missile launched hypersonic glider is exactly what the US is testing under the HTV-2 program, and it’s a concept which goes back to the X-20 Dynasoar which in turn was based off the Nazi Silverbird concept from WW2. In general the things would work the same as the way the space shuttle reenters. Its totally possible to make such a glider circle the earth if you want though HTV-2 is not intended to be recovered.

Such attack gliders will be heavy, very expensive and very complicated but the return is you can still have all the range and most of the speed of an ICBM and yet the ability to turn at as much as 2-3Gs. That isn’t much by aircraft standards, though it would not be bad by bomber standards, but it’s enough to make life utter hell for current ABM systems. Gliders like this can also exploit the fact that most ABM systems either only work in the atmosphere, or only work above the atmosphere leaving a grey area in-between. Depending on the exact trajectory, a glider may be able to glide through the gap and simply be immune to interception due to flight control constraints of the ABM interceptors.

The only ABM system being advertised as able to hit targets both endo and exo atmospheric, and switch engagement modes in flight is the US THAAD. This is a major reason why THAAD has taken almost 20 years to perfect while less ambitious systems like SM-3 have become functional in less time.

http://sitelife.aviationweek.com/ver1.0 ... e.Full.jpg

This chart shows the two planned flight paths of the HTV-2 test vehicles, the first one goes right at the target, the second flight demonstrates the cross range turning capability. The first test already occurred and failed after 10 minutes because of unanticipated yaw leading to automatic self destruct, but the second test is a go for early 2011. Plans are for only conventional versions at the moment… that will last as long as it takes foreign ABM systems to make US ICBM and SLBM weapons ineffective. The HTV-2 was launched from a Minotaur rocket, which is a space booster we built using surplus rocket motors from retired Peacekeeper ICBMs.

An hypersonic glider is not a missile so you're talking about completely different things. Your glider has to be taken to the operational speed somehow and it has to be complex and made of quite exotic materials if you want range. We don't reach hypersonic now with missiles, only with flight demonstrators scramjets and real operational models are at least a decade away.

A hypersonic missile does not have to be air breathing; no air breathing hypersonic missile is currently in service but such a weapons did fly in the 1980s when one of the ASLAM prototypes broke mach 5.5 before it blew up. Intended design speed was only mach 4.5. Plenty of hypersonic rocket powered missiles exist.

[Shroom Man 777]

If you want to deliver a nuclear weapon by stealth, then you've already got the B-2 and stealthy cruise missiles. They're both subsonic, but if you want your stealth nuke to go supersonic/hypersonic then the friction and heat basically makes the idea of stealthing useless.

[Stuart]

Fin actuation systems at high operating temperature and speeds are very complex for a relatively small structure. I've heard proposals to add side thrust rocket modules, if you use a gel propellant integrated in the missile's body then you get an easy to control lateral maneuverability without the stability and storage problems of using a liquid propellant for this function.

The trouble here is weight and volume. When designing RVs, we spend large sums of money shaving small fractions of an ounce off the weight of the system. Literally, the weight of a few grains of dust is significant because each additional weight increment costs range and acceleration. Those costs are cumulative and the multiplier factor is high so a relatively small weight gain results in a large performance loss. The catch is that the RVs are unguided so giving them a maneuvering capability means also giving them a guidance system so that they can correct their aim after having evasively maneuvered. That's a lot of additional weight.

What this generally means is that the adoption of existing maneuvering technology for evasive purposes (I'll explain that caveat later) results in a loss of warhead capacity. In other words, a missile that throws (say) eight warheads in MIRV configuration may only be able to throw three evasively maneuvering warheads. That means the defense has effectively shot down five warheads before the attack even begins. Our old friend virtual attrition again.

There's another catch here; faced with an MIRV we don't shoot down each warhead individually. That's boring and can cause carpal tunnel syndrome. We shoot the bus (not a tug by the way) down and score all the RVs at once. That's why the ABM treaty was devised by the way; MIRV doesn't work in the face of a competent ABM defense and people wanted MIRVs so they treatied away the ABMs. Now, evasive maneuvering of a bus would really screw up the launch pattern of the RVs (remember those things are unguided). So, if the evasive RVs were integrated with a MIRV bus, the evasive technology does them no good at all since they'll still be on the bus when it does the big firework in the sky. So, an evasively maneuvering RV is basically one per missile.

Now, one has to ask the question, is the increased difficulty of shooting down the RV a compensation for the loss of warheads caused by going to an evasive RV. To date, the answer has always been no.

Maneuvering RVs do have a role though but it isn't evasion (see, I said we'd get back to this). It's to increase terminal accuracy. The MARVs (maneuvering re-entry vehicles) are used to put the warhead exactly where we want it. When I say exactly, I mean the CEP is measured in single digits of feet. This is really useful when it comes to erasing pinpoint targets like buried hearquarters buildings, political high-value targets, bunkers etc. In this context, one device that does land on top of its target really is worth a dozen a lot further away. In fact, with some of these MARVs we can forgo the nuclear device and give it a high explosive warhead. Dropping an HE charge from orbit down a manhole is actually possible using this kind of technology. It's just very expensive. It's much cheaper to blow up the whole city but the catch is, the kinds of targets we're interested in here may not be destroyed by the comprehensive urban redevelopment approach.

[Eternal_Freedom]

"the comprehensive urban redevelopment approach"

Seriously, that is a fucking hilarious way to say it