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by magnetic·8y ago·view on hn ↗
Can you explain why the update rate is 10 Hz? It seems orders of magnitude away from current tech, and even from tech of 20 years ago.

Perhaps I misunderstood what the update rate was, but I interpreted as the rate at which the "chaser" can update its trajectory or take action (kind of like the main loop running 10 times a second).

1 comments
It's only "about" 10 hZ, on that order of magnitude. Indvidually you can have faster components and even though the process is pipelined, the last guidance correction that matters takes the sum total of all component times in the system. The seeker has to see the target is off-axis, then the computer has to calculate the proportional control input, and then the servos actuate the fins.

You also might be overestimating what "current tech" means in military hardware. The PAC-3 Patriots were entered into service from 1995-2000, meaning they were designed with late 1980's technology. The Saudis don't get to have the true top end hardware, the US won't sell their "best stuff" until they have "new best stuff" to beat it.

Whats our current "best stuff" in missile tech?
I wonder if the laser weapon systems will go anywhere in the end. Certainly seems easier to target, and cheaper to shoot. But there's still a lot of energy that needs to go into a missile to be certain it's disabled.

https://en.m.wikipedia.org/wiki/Laser_Weapon_System

An ICBM warhead is going to be a tough target for that. Very fast so you don't have long to heat it and fitted with heat shielding for reentry already.
It depends on what kind of missile you want to hit. A scud is very different from an ICBM, which are both quite different from anti-ship and some of the area denial weapons.
In perspective: The Russian Satan 2 is indefensible, and also the older SS-N-27 Sizzler shot from very nearby submarines. Not enough time to react on those.
There's really no such thing as an indefensible missile, just like there's no such thing as an impenetrable computer network. Difficult to defend against, those exist. Missiles with an extremely low probability that we can physically intercept, those exist. But defending against a missile starts as soon as a possibility of launch occurs, and you can bet that a lot of people spend a lot of time figuring out how to defend against "indefensible." They aren't perfect, but they aren't going to bat .000 either.
Well, Russians claim otherwise and Wikipedia confirms. It's of course highly contra-productive to tell such things the American public.