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Comment by DennisP | Hacker News Reader

So why don't ground-to-air missiles make all fighters obsolete?

(If the answer is that they lack "mid-course updates from it's firing aircraft," that sounds like something that could be jammed.)

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AA missiles start with a huge energy disadvantage. They start with a velocity and altitude of 0 so they need an engine powerful enough to catch the fighter and enough fuel to reach it's altitude. More power means more weight, more weight means more fuel, that equation results in a huge missile with minimal maneuverability.

No maneuverability = no hit. Surface to air missiles are intended to target low, slow, or bulky targets and fighters are outside those categories.

Sounds like what's needed is a bunch of high altitude blimps or cargo planes with air-to-air missiles.

And enough countermeasures they don't get picked off by ground-to-air missiles.

Or two-stage AA missiles with large "get it up in the air and fast ASAP" 1st stages and smaller "aim at the baddy" 2nd stages?

Communication between plane and rocket has several options, one of which is effectively a laser pointer in the aircraft pointed at one in the rocket modulated with the information to be transmitted.

It's fast, lots of bandwidth, and it's totally unjammable. Or even detectable for that matter.

Unjammable by clouds? Wouldn't going into clouds be a way to evade in this case?

Depends on the frequency. Clouds are famously transparent for ultraviolet for instance. The sun floods the sky with it of course, but there's plenty of choice. But at the ranges we're talking about 10-20, maybe 100km ... yeah pretty much unjammable by clouds. Sufficiently intense rain or something like a snow storm would probably work though.

I doubt you'd be flying in the conditions that would block a laser from hitting it's target. In practice, there really aren't that many ways to "jam" a rocket, radio jamming really can't hit all the bands, and frequency-hopping SDR is very, very cheap now.

To my mind your best hope would be an EMP or a small missile-tracking gun.

> frequency-hopping SDR is very, very cheap now.

Which also makes broadband frequency-hopping jammers similarly cheap.

Frequency hopping doesn't make jammers more effective. So long as you cannot prevent the pattern of the transmitter, your only option is to jam all frequencies, which means you have a massive disadvantage in the power you need to emit, to the point that simple directional antennas probably make your task flatly impossible.

Laser communications are being studied because they are impossible to detect, not because the existing communications are too easy to jam.

(late edit:)

*predict

Because ground-to-air missiles need to be put on the ground before the engagement, and that's not always possible, I guess.

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