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Hypersonic HAWC missile flies, but details are kept hidden

airforcemag.com

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Re: Hypersonic HAWC missile flies, but details are kept hidden

#81

Post by krisoft »

tptacek wrote: post #10
echelon wrote: post #2

As I understand it, China has hypersonic missiles and nukes, whereas the US does not. Should a conflict in the South China sea break out, China could nuke US carrier groups assuming their satellites aren't taken out first. That spells game over for US projection of power if successful. China could deploy air and submersible drones to get around downed satellites, but these have the potential of being jammed with EMP,…

Is the premise here that carrier groups would be survivable in the absence of hypersonic missiles? They... aren't at all, are they?

Every time the navy is asked about the survivability of the carrier groups they seem to start talking about the “whole kill-chain” of the enemy weapons. It sounds like they plan to knock out the targeting satelites before they could target them instead of trying to catch the missiles. Or at least thats how I read the tea leaves.

Re: Hypersonic HAWC missile flies, but details are kept hidden

#83

Post by masterof0 »

justicezyx wrote: post #42
AnimalMuppet wrote: post #36

Earlier quoted context omitted.

> Hi, propagandist? Personal attacks are against site rules, and you've been here long enough that you should know that. > China had no ambition for territorial expansion other than defending herself. That's the pattern for 2 thousands years. China occupied Tibet. China invaded Vietnam twice. The first time, they stayed for a thousand years. "China has no ambition for territorial expansion" only if you accept China's…

I think we are just speaking the same thing. You might assume that I sided with China mainland. Well, that not where I stand. Neither do I side with Taiwan, nor US. I stand with the safety and prosperity of people.

It doesn't matter, you are not allowed to point out hypocrisy, as is not immoral to criticize another government while your own kills children with drone strikes. Is the way it is, I learned the good old *downvoted* way. There is, it seems, a list of things you cannot criticize over here: Rust, US, React JS, Firefox, Elon Musk, Tesla, etc...

Re: Hypersonic HAWC missile flies, but details are kept hidden

#84

Post by dd444fgdfg »

echelon wrote: post #2

As I understand it, China has hypersonic missiles and nukes, whereas the US does not. Should a conflict in the South China sea break out, China could nuke US carrier groups assuming their satellites aren't taken out first. That spells game over for US projection of power if successful. China could deploy air and submersible drones to get around downed satellites, but these have the potential of being jammed with EMP,…

IMHO, the risk of nuclear war is higher than we think. Can you imagine the number of expected casualties of all-out-war with China? We've played this game before. Japan/WW2. The US _will_ nuke China and justify it under number of lives saved.

Re: Hypersonic HAWC missile flies, but details are kept hidden

#85

Post by jamiek88 »

lampington wrote: post #66
justicezyx wrote: post #46

Earlier quoted context omitted.

The hypersonic missle won't carry nuclear war head. The impact is enough to render a CV lose combat capability. The modern weaponry are delicate machines. A 50s computer might withstand an earthquake. The modern one probably won't survive a drop less than 1 meter.

A 50s computer would have been largely glass vacuum tubes and dropping it would cause quite a lot of problems. And a modern computer would be fine in an earthquake if it didn't fall off something or have something heavy fall on it.

Yeah was just thinking that! That analogy may have worked 20 years ago but everything, including notably storage, is solid state now and way more durable.

Re: Hypersonic HAWC missile flies, but details are kept hidden

#86

Post by dragonwriter »

dd444fgdfg wrote: post #84
echelon wrote: post #2

As I understand it, China has hypersonic missiles and nukes, whereas the US does not. Should a conflict in the South China sea break out, China could nuke US carrier groups assuming their satellites aren't taken out first. That spells game over for US projection of power if successful. China could deploy air and submersible drones to get around downed satellites, but these have the potential of being jammed with EMP,…

IMHO, the risk of nuclear war is higher than we think. Can you imagine the number of expected casualties of all-out-war with China? We've played this game before. Japan/WW2. The US _will_ nuke China and justify it under number of lives saved.

> . Can you imagine the number of expected casualties of all-out-war with China? We've played this game before. Japan/WW2. The US _will_ nuke China

Japan didn't have a nuclear second-strike capability with the range to hit the US. (Or, literally, any part of that taken independently.)

The US leadership can't even make a remotely plausible argument, after emerging from their bunkers after the exchange is done, to have “saved lives” by nuking China.

Re: Hypersonic HAWC missile flies, but details are kept hidden

#87

Post by thunderbird120 »

hmm320 wrote: post #82

Don't the Russians have missiles that fly >5x faster than this, at mach 27? https://www.popularmechanics.com/military/weapons/a30346798/...

Air breathing hypersonic missiles and hypersonic glide vehicles really shouldn't be compared. They have different operational uses. Air breathing missiles are slower but can also be significantly smaller and can fly for sustained periods at lower altitudes. This missile is more comparable to the Russian Zircon missile.

Re: Hypersonic HAWC missile flies, but details are kept hidden

#88

Post by foobarian »

rektide wrote: post #33
x86_64Ubuntu wrote: post #19

What does hypersonic mean? I thought all missiles were largely supersonic, except for maybe cruise missiles.

One key consideration that I only got recently is the difference between a cruise & ballistic missile. A ballistic missile launches at great velocity, then more or less falls at it's target (over an extended distance) using a ballistic trajectory. A cruise missile is under power for a large part of it's journey, typically flying much lower, & able to navigate/direct itself. A ballistic missile is often quite superson…

I was pretty surprised by how slow cruise missiles are when I read up on them recently - similar to big airliner speeds. I always had a mental image of missiles as these "fastest in the sky" things that you could only dodge but not outrun. It's possibly true for Sidewinders but even they top out around Mach 2.5, so the hypersonic developments are a huge step forward.

Still kinda surprised there aren't fast missiles that use rocket engines. It works for ICBMs? I don't see a reason they couldn't maneuver as well. Maybe the hypersonic regime makes things novel not just for propulsion but control too.

Re: Hypersonic HAWC missile flies, but details are kept hidden

#89

Post by MilStdJunkie »

twic wrote: post #80
MilStdJunkie wrote: post #59

Earlier quoted context omitted.

There's a sort of fuzzy line betwwwn high supersonic and hypersonic, but the secret sauce that definitely separates them - and the hardest part by far - is supersonic combustion in the scramjet. You basically have to figure out how to make something sit still long enough to impart a thrust impulse, while at the same time sitting in an airstream that's starting to act like a cutting laser. Very little tech data from w…

The SABRE engine won't liquefy incoming air, it just cools it down a lot (to -150 C!). But SABRE is an evolution of a 1980s design, the RB545, designed for the HOTOL spaceplane, which would indeed have liquefied incoming air. The RB545 was in turn derived from a 1950s concept, LACE: https://en.wikipedia.org/wiki/Liquid_air_cycle_engine

Ha, thanks for the correction! I haven't been following the project all that closely, but I always liked it. It seems to me like a more . . durable . . solution to the hypersonic propulsion problem, almost an extension of the hybrid turbo-rams of the SR71. I mean, the alternative, relying on converging shock fronts to serve as a flame holder . . so, ok, I am not an expert, but that sounds iffy.

Re: Hypersonic HAWC missile flies, but details are kept hidden

#90

Post by SonicScrub »

hmm320 wrote: post #82

Don't the Russians have missiles that fly >5x faster than this, at mach 27? https://www.popularmechanics.com/military/weapons/a30346798/...

That vehicle is a sub-orbital vehicle with a re-entry trajectory similar to a ballistic missile . It reaches it's highest speeds only at altitudes where the atmosphere is more individual particles than a continuous gas (it's apogee of 62 miles is well above the Karmen line). The definition of Mach number only makes sense within a fluid. A vehicle that travels 20,716 miles per hour is NOT travelling Mach 27. You can say it's travelling roughly 27 times the speed of sound at sea-level like conditions to get a sense of the scale of the speed, but it is not travelling Mach 27. Once it slams into the atmosphere on re-entry, you can say it is travelling at Mach 27, but by then it's not undergoing sustained flight. This specific vehicle is merely gliding.

This distinction is important, because all of the difficulties associated with flying at hypersonic speeds are due to the problems associated with flying through the fluid. It's comparatively easy to accelerate to the high speeds of sub-orbital vehicles once outside a meaningful atmosphere.

Militarily this is an important distinction as well. An intercontinental ballistic missile needs to go significantly above the earth's atmosphere. During this phase, it's easily detectable, since the horizon is much further away. A vehicle flying much lower well within the earth's atmosphere at very high speeds gives much less early warning.

This specific vehicle strikes a sort of middle ground between these concepts. It's half sub-orbital ballistic missile (it's still required to go above a meaningful atmosphere), half hypersonic cruise missile. Although very critically it is not undergoing sustained flight at hypersonic speeds

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