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Can You Stop a Hypersonic Missile?

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Re: Can You Stop a Hypersonic Missile?

#71

Post by caconym_ »

axus wrote: post #52
caconym_ wrote: post #47

Earlier quoted context omitted.

> ofc, I used LLMs to help reformulate some sections This is not really meant to single you out, since there's a lot of this going around, but I really don't think this should be a matter of "of course". Why should it be the default to let a tool that doesn't have your context, or your voice, override your own usage of language?

He met the goal of conveying a lot of information. If he's only judged on what he said, and not how he said it, he did great. If I want to hear someone's voice, I'll watch YouTube.

> If I want to hear someone's voice, I'll watch YouTube.

I'm sure that in your head this is a witty rejoinder, but it really is quite a wild thing to say: that you place no value on the individual variations in how different human writers express themselves. It follows that you really don't care about voice on YouTube either, except in the most basic mechanical sense: you would be happy watching videos written by AI and narrated by the same monotone text-to-speech narrator, video after video, efficiently delivering that densely packed information you crave.

This is actually a thing, isn't it? Like those "shorts" with the AI narration and matching subtitles flashing by in the middle of the screen. I guess you must love those---somebody does, probably a lot of people, or they wouldn't exist.

I'm tempted to frame this as a new kind of illiteracy. People whose brains are so addled by the modern media landscape that to get them to pay attention to anything at all you have to resort to tricks like this; god forbid they ever encounter a writer or narrator who speaks differently, sounds differently, thinks differently, frames differently. Nobody should be surprised, I suppose, that the ability to parse different levels of meaning in Content that falls outside the AI cognitive monoculture is a dying skill.

Re: Can You Stop a Hypersonic Missile?

#72

Post by jjk166 »

echoangle wrote: post #68
jjk166 wrote: post #62

> Ground radar is line-of-sight. The Earth is round. Anything below the horizon is invisible. That's not true. Ground based radar can see over the horizon (hence the term Over-the-horizon radar) by taking advantage of the refractive index of air, allowing the radar waves to essentially curve along, as well as by bouncing radar waves off the ionosphere. Given that this is the foundation of TFA's argument, it does not…

On the other hand, those only really tell you that something is coming somewhere in that direction, OTH radars don't have the resolution for targeting afaik.

Knowing that it's coming and the general direction is what you need for command and control, the actual interceptor is going to be much more limited in range than the targeting radar.

Re: Can You Stop a Hypersonic Missile?

#73

Post by jjk166 »

adrian_b wrote: post #70
jjk166 wrote: post #62

> Ground radar is line-of-sight. The Earth is round. Anything below the horizon is invisible. That's not true. Ground based radar can see over the horizon (hence the term Over-the-horizon radar) by taking advantage of the refractive index of air, allowing the radar waves to essentially curve along, as well as by bouncing radar waves off the ionosphere. Given that this is the foundation of TFA's argument, it does not…

Over-the-horizon radars have very poor resolution, so they are useful only for early warning, not for guiding an interceptor. For targeting at distance, you need antennas mounted on high masts or airborne radars.

You don't need to target at distance, you are limited by the range of your interceptor. OTH tells you which interceptor battery needs to be looking where.

Re: Can You Stop a Hypersonic Missile?

#74

Post by adrian_b »

eightysixfour wrote: post #43
anonymousiam wrote: post #33

Lasers can stop a hypersonic missile, but the challenge is getting a beam on the target through the atmosphere. Some of the old SDI tests solved the problem by flying the laser above most of the atmosphere. https://en.wikipedia.org/wiki/Boeing_YAL-1

What is the math on how much additional heat a laser would deliver to a warhead which is presumably designed with some kind of ablative shielding that is pushing through air compressed into a plasma? It seems like the damage from a laser pointed from miles away through atmosphere wouldn't be enough to change anything.

This is mentioned in TFA.

The current lasers are not powerful enough for this purpose, they may be efficient only against drones or other slower targets.

Re: Can You Stop a Hypersonic Missile?

#75

Post by adrian_b »

jandrewrogers wrote: post #57
Rotdhizon wrote: post #17

I imagine the realistic answer is "we don't know", because it's never been truly tested. They are constantly improving and iterating designs, speeds, anti-intercept tech, anti-tracking. As you said as well, this is only what from is available in OSINT reporting. There are surely classified weapons from all major countries lying in wait for the most serious scenarios. A big part of hypersonic/ICBM warfare is anti-dete…

Detecting hypersonics is relatively easy because they are the opposite of stealthy. Even most glide vehicles have an initial ballistic trajectory that exposes it to many sensors at distance. The US field-tested a number of short range hypersonics since the 1990s that don't have a ballistic trajectory but those were all canceled. Hypersonics have two related technical challenges. They are not maneuverable, at least no…

In TFA, only the missiles with terminal guidance are discussed, of which three models are currently known, one in each of USA, Russia and China, none of which has been deployed yet.

Re: Can You Stop a Hypersonic Missile?

#76

Post by adrian_b »

sidewndr46 wrote: post #64
visviva wrote: post #13

Earlier quoted context omitted.

The weapon you linked to is an anti ballistic missile. The difficulty is not purely in how fast the target is going, but how much it maneuvers, the duration at which it can sustain those speeds, and the altitudes at which it operates. The article addresses this early on.

Aren't all hypersonic missiles based on re-entry vehicles? The altitudes they operate at are basically 'all of the above'. If someone can launch a low altitude missile that can sustain Mach 5+, I'm not sure what you are going to do against it. So what are the hypersonic low altitude capabilities for maneuvers for these platforms? I don't deny the maneuver but I have this hard time believe someone just throws out some…

TFA does not discuss the missiles that only reach a hypersonic speed, which is true for any ballistic missile, because such missiles have existed for a very long time.

It discusses the hypersonic missiles that are maneuverable, which for now have not been deployed in combat yet, by any of the 3 countries known to possess such missiles.

Re: Can You Stop a Hypersonic Missile?

#77

Post by protortyp »

echoangle wrote: post #68
jjk166 wrote: post #62

> Ground radar is line-of-sight. The Earth is round. Anything below the horizon is invisible. That's not true. Ground based radar can see over the horizon (hence the term Over-the-horizon radar) by taking advantage of the refractive index of air, allowing the radar waves to essentially curve along, as well as by bouncing radar waves off the ionosphere. Given that this is the foundation of TFA's argument, it does not…

On the other hand, those only really tell you that something is coming somewhere in that direction, OTH radars don't have the resolution for targeting afaik.

Exactly. In an earlier draft I went deeper into this, but cut that section among others for brevity.

Re: Can You Stop a Hypersonic Missile?

#78

Post by protortyp »

jjk166 wrote: post #62

> Ground radar is line-of-sight. The Earth is round. Anything below the horizon is invisible. That's not true. Ground based radar can see over the horizon (hence the term Over-the-horizon radar) by taking advantage of the refractive index of air, allowing the radar waves to essentially curve along, as well as by bouncing radar waves off the ionosphere. Given that this is the foundation of TFA's argument, it does not…

I cut this on purpose due to the poor resolution other commenters have mentioned already.

Re: Can You Stop a Hypersonic Missile?

#79

Post by LorenPechtel »

What in the world is the author thinking?

We have detect/analyze/slew as three separate steps that must run in order. You don't consider whether the item is a decoy until you have plenty of tracking on it?? And if slew is even a step (I am aware of no US missile in this realm that moves it's a launcher) you can likewise do that while confirming your target.

And he's assigning a fixed flyout time--but flyout time is entirely a function of where your launcher is relative to the missile target. It's coming down your throat (launcher next to the target), flyout is nearly zero. Note that we saw Iron Beam successfully engage Iranian ballistic missiles. Targets aren't up in the sky, the missile has to come down into the envelope of the weaker weapons in order to actually hit something. (The original issue of targeting ICBMs didn't consider this because the warhead would salvage fuse. Useful if the payload is nuclear, basically useless otherwise.)

Re: Can You Stop a Hypersonic Missile?

#80

Post by Idilunlu »

raffael_de wrote: post #60
swatcoder wrote: post #42

Earlier quoted context omitted.

> and yes ofc, I used LLMs to help reformulate some sections ??? Why in the world would that be an "ofc"? If you're trying to establish yourself as a writer and communicator, LLM's are the last thing you want to color your personal voice with. They may have a role in cleaning up interpersonal communication or in helping non-professional communicators shape up their prose for formal occasions, but they are not some ki…

I also don't understand this. After having written something I never felt a need to have it reformulated by anything. What would even be the prompt for that?

I think it's easy for native speakers to say. But as English is not my mother tongue, I find it safer to run it through a checker and nowadays, LLMs. So maybe no need to be so harsh about it
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