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Missile defense is NP-complete

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Re: Missile defense is NP-complete

#441

Post by mattmaroon »

egorfine wrote: post #360
15155 wrote: post #324

Earlier quoted context omitted.

Ukraine has no feasible means to actually act offensively, meanwhile, the United States is a nuclear weapons state. Pose a credible-enough threat and atomic deletion will ensue.

> meanwhile, the United States is a nuclear weapons state This logic is outdated because it is pretty obvious that no one is going to employ nuclear warheads in a typical conventional war and thus the nuclear factor suddenly doesn't matter for war economics.

They’re not going to drop nukes but he’s right about the concept otherwise. We only have to intercept missiles until we blow them (and the factories that make them) all up which we can conceivably do just fine without nukes. That’s the strategy here, which is obvious but whether or not it can be achieved is less so.

Re: Missile defense is NP-complete

#442

Post by don_esteban »

maratc wrote: post #431
don_esteban wrote: post #233

Earlier quoted context omitted.

Depends, blanketing Ben Gurion (or any airbase) with parked aircraft on the tarmac with carpet munition is a really bad day. But yes, against protected targets cluster munitions do not achieve much. If you have relatively few low-precision missiles, using single warheads means you are risking achieving NO damage (easier to intercept, a good chance that it will hit nothing), with a cluster munition you are guaranteein…

Tarmacs are really hard to hit exactly, especially so when you fire from 1500 miles away. Each angular second turns into a big miss. Also, the launch goes towards the area where GPS denial is assumed. This denial can come in many forms. There were reports about three small aircraft being damaged in Ben Gurion, one of them caught a fire. I guess three millionaires will have nothing to fly until they collect their insu…

There is no point in trying to argue that such an attack is extremely difficult, it already happened, and an attack on Prince Sultan Air Base near Riyadh damaged/destroyed E-3 Awacs and several tankers (see e.g. https://www.wsj.com/livecoverage/iran-war-middle-east-news-u...).

It is not 1500miles away from Iran, but neither is Ben Gurion (Ben Gurion is cca 200-300km further away from the closest point in Iran that Prince Sultan).

Re: Missile defense is NP-complete

#443

Post by fpoling »

don_esteban wrote: post #435
fpoling wrote: post #434

Earlier quoted context omitted.

APKWS launching from air is a stop-gap measure in any case. The detection range for Shahed-type drones is tenths of kilometers, not hundreds, like with fighter jets or big missiles. One cannot have that many fighter jets in the air all the time even without the threat of manpads. But ground-based platforms work just fine and cheap enough to scale up the deployment to cover the big area. The big advantage of APKWS ove…

First, if I understand correctly, APKWS is laser guided (one of the reasons it is relatively cheap is cheap simple guidance), it needs the carrier to designate the target. Second, it is rather short range, and that range is helped significantly by the speed and altitude of the launching platform. Launching from the ground upwards would significantly reduce its range, which is anyway just a few km. Due to the short ra…

The latest APKWS is IR guided and works in fire and forget mode that works nicely from the ground. And then drone interceptor struggles with Russians Shaheds with jet engines.

On the other hand the latest development with drone interceptors is rocket booster to quickly bring in within Shahed. So I guess there would be a convergence between APKWS and interceptor drones.

Re: Missile defense is NP-complete

#444

Post by don_esteban »

fpoling wrote: post #443
don_esteban wrote: post #435

Earlier quoted context omitted.

First, if I understand correctly, APKWS is laser guided (one of the reasons it is relatively cheap is cheap simple guidance), it needs the carrier to designate the target. Second, it is rather short range, and that range is helped significantly by the speed and altitude of the launching platform. Launching from the ground upwards would significantly reduce its range, which is anyway just a few km. Due to the short ra…

The latest APKWS is IR guided and works in fire and forget mode that works nicely from the ground. And then drone interceptor struggles with Russians Shaheds with jet engines. On the other hand the latest development with drone interceptors is rocket booster to quickly bring in within Shahed. So I guess there would be a convergence between APKWS and interceptor drones.

Yes, the technology is evolving fast.

IR guided fire and forget is fine, but undoubtedly quite a bit costlier than the basic laser-guided one. If you want to use it against jet engined Shaheds while launching from the ground, you definitely need larger rocket motor, i.e. costlier interceptors. But that might be fine, the jet engined Shaheds are not as cheap as the basic ones anyway.

Actually, I am surprised they still use the Shahed platform for the jet engined drones. A Reaper-like platform with high aspect ratio wings would be much more aerodynamically efficient, allowing longer range/loiter time/larger payload. It is definitely more expensive airframe, but that jet engine might be the main cost factor anyway.

Re: IR seeker against plain Shaheds: does the basic weedwhacker Shahed have enough IR signature? (More precisely: does it have it if you did some basic precautions - cover the engine, some mixing of the ambient air with the exhaust.) The power level of that engine (= the whole source of IR energy) is quite low...

Re: Missile defense is NP-complete

#445

Post by fpoling »

don_esteban wrote: post #444
fpoling wrote: post #443

Earlier quoted context omitted.

The latest APKWS is IR guided and works in fire and forget mode that works nicely from the ground. And then drone interceptor struggles with Russians Shaheds with jet engines. On the other hand the latest development with drone interceptors is rocket booster to quickly bring in within Shahed. So I guess there would be a convergence between APKWS and interceptor drones.

Yes, the technology is evolving fast. IR guided fire and forget is fine, but undoubtedly quite a bit costlier than the basic laser-guided one. If you want to use it against jet engined Shaheds while launching from the ground, you definitely need larger rocket motor, i.e. costlier interceptors. But that might be fine, the jet engined Shaheds are not as cheap as the basic ones anyway. Actually, I am surprised they stil…

Shahed shape is dictated by the need to sustain very high G and aerodynamic forces during the launch from a truck which in turn allows for a very fast deployment. Anything more aerodynamic will imply stronger, more expensive frame and less payload.

Shahed has sufficiently bright IR that even a basic seeker works. To keep the cost low no efforts were applied to minimize the signature.

It is fascinating how well designed Shahed was for its intended purpose of being the cheapest mass-produced platform that would saturate any advanced air defenses while hard to track launch site. However, with appearance of cheap mass-produced counter-measures it may no longer be optimal.

Re: Missile defense is NP-complete

#446

Post by ssvss »

jandrewrogers wrote: post #96
jmyeet wrote: post #76

Earlier quoted context omitted.

In strategic circles, this was a common thought in the 12 day war: Iran was essentially mapping and testing defenses. As evidence of this, the US was forced to hastily move THAAD ground station radar from South Korea because Iran destroyed a bunch of them in the Gulf [1][2]. Bear in mind there aren't many of these and they cost half a billion dollars each . Further evidence of this is how quickly it happened. Iran mo…

> Iran destroyed a bunch of them If by "a bunch" you mean one.

Literally a bunch,

https://edition.cnn.com/2026/03/05/middleeast/radar-bases-us...

https://xxtomcooperxx.substack.com/p/the-awacs-scare

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