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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

#71

Post by dirtyid »

echelon wrote: post #53
dirtyid wrote: post #51

Interesting to ponder the US need for hypersonic capabilities. PRC + Russia needs it to asymmetrically challenge the USN. Not many time-sensitive targets for the US to hit in PRC or Russia outside of mobile TELs to take out road mobile nuclear forces. For context, US dumping ~4B into hypersonics = ~3000 JASSMs which is probably a better investment for peer naval warfare. Politically, this program feels like air force…

The PRC is developing a blue water navy and is heavily ramping up on carrier shipbuilding. It makes sense that the US would want to build similar, land-based defensive strategies as a deterrent.

>The Air Force has said it plans to pursue both the ARRW and the Hypersonic Attack Cruise Missile (HACM), as initial and future hypersonic attack capabilities, respectively.

These are offensive standoff weapons launched from air designed to hit time sensitive targets. The question is really what targets, like I said, spending the money on 3000 JASSMs is already enough to sink every major PLAN combatants with room to spare. Need to consider what these hypersonics can hit that traditional standoff weapons can't. Or just the politics behind aquisition between branches. I'm not saying this is bad/wasteful defense spending, but curious what it's exactly for.

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

#72

Post by throwawaycuriou »

Armisael16 wrote: post #52
throwaway210222 wrote: post #40

Earlier quoted context omitted.

> 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. Incorrect, the USA will probably just shrug, and call in the other 11 super-carriers and 9 amphibious assault ships. At the same time they will invoke NATO article 5 and a few other Asian mutual-defence treaties. 2 UK, 1 Spanish, 1 French, and 2 Italian carriers will a…

Article 5 only applies to attacks in Europe or North America. The SCS is definitely in neither.

Interesting. Edge case: if French Guyana (off the north side of South America but considered part of France and the European Union) is the victim of an attack by some means, are NATO members obliged to act in its defense?

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

#73

Post by wahern »

bb101 wrote: post #16
dragonwriter wrote: post #12

Earlier quoted context omitted.

> Should a conflict in the South China sea break out, China could nuke US carrier groups If China wants to start a nuclear exchange, sure. The US probably wouldn't go nuclear in response to an invasion of Taiwan, but it absolutely would in response to a nuclear attack on US forces.

And our reality would segue into the storyline of Threads. The 1984 BBC film should be mandatory viewing for all people in positions of power. The bombing is only the start of the horror. https://www.youtube.com/watch?v=vgT4Y30DkaA

The Cuban Missile War Timeline: https://www.alternatehistory.com/forum/threads/the-cuban-mis...

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

#74

Post by dirtyid »

aidenn0 wrote: post #65
dirtyid wrote: post #51

Interesting to ponder the US need for hypersonic capabilities. PRC + Russia needs it to asymmetrically challenge the USN. Not many time-sensitive targets for the US to hit in PRC or Russia outside of mobile TELs to take out road mobile nuclear forces. For context, US dumping ~4B into hypersonics = ~3000 JASSMs which is probably a better investment for peer naval warfare. Politically, this program feels like air force…

Would a hypersonic SAM improve CV survivability against non-hypersonic cruis missiles?

This is an entirely different program than hypersonic defense on naval platforms. As far as I know Pentagon is focusing on lasers and advanced interceptor designs, and hopes to have something "workable" by the mid 2025s.

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

#75

Post by alexisread »

MilStdJunkie wrote: post #59
TrainedMonkey wrote: post #35

> The HAWC is exploring air-breathing hypersonic flight > propelling the cruiser at a speed greater than Mach 5 I wonder if they are running a scramjet engine: https://en.wikipedia.org/wiki/Scramjet

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…

As far as I know, the Sabre heat exchanger doesn't liquefy the air as frost kills the tubing. It cools down to the boundary without going over. I believe they've demonstrated mach 3 conditions but not mach 5, and they're on track

https://www.pprune.org/military-aviation/print-619462-reacti...

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

#76

Post by randomopining »

bllguo wrote: post #30
emaginniss wrote: post #4

Earlier quoted context omitted.

What if they decide they want to gobble up Taiwan, Vietnam, Japan, Australia, etc? Should we just sit back and say "it's not us, so this is fine?"

I think citizens of the most violent nation in recent history should do some introspection before projecting their misdeeds onto others..

Nope. False premise. US is the best we have.

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

#77

Post by Armisael16 »

throwawaycuriou wrote: post #72
Armisael16 wrote: post #52

Earlier quoted context omitted.

Article 5 only applies to attacks in Europe or North America. The SCS is definitely in neither.

Interesting. Edge case: if French Guyana (off the north side of South America but considered part of France and the European Union) is the victim of an attack by some means, are NATO members obliged to act in its defense?

No. The same is true of New Caledonia (most of overseas France, actually).

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

#78

Post by colechristensen »

dsr_ wrote: post #22
x86_64Ubuntu wrote: post #19

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

It's a speed regime. Under Mach 1 is subsonic. From Mach 0.9 through 1.2 or so is transsonic. 1.0 and greater is supersonic. Above Mach 5ish is hypersonic. Mach 25 is approximately orbital velocity, but since Mach is actually related to air pressure, it's not a very meaningful comparison except to note that anything moving that fast isn't going to be in-atmosphere for very long.

The speed of sound in air (or mixtures of diatomic gasses) is a function of temperature only, independent of pressure and density. Or it depends on pressure and density in a way which cancels out and leaves only temperature as an independent variable for equivalent mixtures of gasses. (i.e. the speed of sound is the same at 20 atmospheres or 0.1 atmosphere as long as the temperature is the same) This becomes untrue when air is very very hot or very very cold, but generally those conditions aren't experienced on this planet outside of hot hypersonic flight.

Water vapor content, not being a diatomic gas does very slightly change the speed of sound but usually to a degree which can be ignored.

(people generally don't believe that the speed of sound in air depends only on temperature when you tell them)

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

#79

Post by nielsbot »

credit_guy wrote: post #24
x86_64Ubuntu wrote: post #19

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

A good starting point is this Congressional report on hypersonic weapons, updated one month ago: https://sgp.fas.org/crs/weapons/R45811.pdf

OMG "The Pentagon’s FY2022 budget request for hypersonic research is $3.8 billion"

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

#80

Post by twic »

MilStdJunkie wrote: post #59
TrainedMonkey wrote: post #35

> The HAWC is exploring air-breathing hypersonic flight > propelling the cruiser at a speed greater than Mach 5 I wonder if they are running a scramjet engine: https://en.wikipedia.org/wiki/Scramjet

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

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