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Comment by WJW | Hacker News Reader

Typically you'd use radar to detect incoming projectiles, using multiple detections over time to determine the trajectory of an incoming missile (they are usually unguided and will thus follow a predictable ballistic trajectory).

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But would it not be possible to build missiles that can intelligently alter route upon detecting detection ? I recall once working on a auto guided industrial machine based on Motorola 68000 microprocessor that could figure out how to route itself to its destination. So unless you can detect and eliminate the missile almost simultaneously, an intelligent missile could throttle it's velocity etc. to avoid predictable trajectory.

Edit: some typos

while missiles can be built to have irregular routes, this is more important for missile-based defense. there, with the distances and speeds involved it will cause the interceptor to need to counter the irregularities, which will make it need to also be much more advanced. small changes in thrust however (at a later time - and thus higher speed) can cause only so much of a change.

but more importantly - light-based interception can be re-pointed much faster then a missile can change it's own course.

A missile design may evolve to have the original missile to intelligently decompose,upon detection, into multiple smaller missiles each with a randomized target and path. The parent missile could focus on reaching as close as possible to target rich area with stealth and upon inevitable detection, unleash smaller missiles with randomized paths. If the cost of missiles keep going down, I can see aggressors firing several of these to maximize their probability of a successful hit.

That's been around for quite a long time, at least the late 1960's.

> A multiple independently targetable reentry vehicle (MIRV) is an exoatmospheric ballistic missile payload containing several warheads, each capable of being aimed to hit a different target. The concept is almost invariably associated with intercontinental ballistic missiles carrying thermonuclear warheads, even if not strictly being limited to them.

https://en.wikipedia.org/wiki/Multiple_independently_targeta...

These are more expensive to build though. At some point, more far-ranging and guided systems can be used to snipe it before it is anywhere close from splitting apart. And Iron Beam will still be cheaper to deal with any warheads that manage to split off.

This is again a money play here, after all everything is a money play.

Iron Beam (this system) is designed to intercept simple rockets, artillery, and etc for cheap. The total cost per shot is estimated at 2000USD overall (including life cycle of the parts, laser, etc) compared to 100000USD for Iron Dome missile alone. It is even more for more advanced stuff like Arrow 2, Arrow 3, or David's Sling (all, including Irom Dome, of which have greater range and capability than the Iron Beam).

The issue with your system is cost.

The rockets that Iran is supplying are unguided ballistic rockets. Artillery is also unguided and ballistic. These are super cheap so its easy and economical to fire a lot of them. This is why Israel wants Iron Beam cause its much cheaper then Iron Dome.

Now lets focus on your solution. The missiles now will need advanced guidance system, maneuvering capabilities (mid course correction, path adjustment), radar and IR warning receivers, and other advanced electronics. None of which are cheap. These components also add weight to the missile, which means bigger missile and more fuel, which adds to the cost of the missile. The need to carry fuel for mid flight adjustment also means heavier missile, which means bigger missile, which means more expensive missile. So your cost per missiles goes up hell of a lot. So now you are limited to the number you can field against Israel. Now its worth it to throw up an Iron Dome against you or possibly an Arrow 2, both which are guided missiles interceptors.

EDIT: Example of the rockets that the Iron Beam is designed to intercept: https://en.wikipedia.org/wiki/Fajr-5

Automated counter-battery in addition to AD would be an interesting extra layer of deterrence.

And a PR nightmare. Shoot a missile from a school or a hospital, then afterwards the newspaper articles write themselves when the automated system retaliates. Radar data showing it was a missile launch site will always lose to pictures of mothers holding dead children.

Counter battery is also of questionable effectiveness when most launch sites are used only once.

> And a PR nightmare. Shoot a missile from a school or a hospital, then afterwards the newspaper articles write themselves when the automated system retaliates.

There's nothing new about Hamas firing rockets from schools and hospitals and Israel responding. It's difficult to exaggerate how dirty the conflict is, and in many respects always has been. It's a positive feedback look because these activities only further dehumanize one from the other's perspective, and it's compounded by people on both sides who capitalize on this dynamic for their own gain.

I have a neighbor who grew up in Israel in the 50s and 60s. If you even mention the words "Arab" or "Palestinian" she'll get visibly angry and bitter. I'm sure the feeling is mutual for many on the other side.

Israel doesn't do counter-battery.

1) Very often the launcher is unattended at the time of launch. You wouldn't get anything but an empty weapon.

2) You can be sure that the counter-battery fire would hit a lot of human shields. Hamas *loves* human shields.

1/ not always, and it limits salvo size, lots of the launchers are multi rocket, so if you can take out the launcher while it still has munitions, you stop rockets, destroy the launcher, damage the site which may be connected to tunnels and maybe people.

2/ like AD you can have red/green zones for pre-authorized counter-battery

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