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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

#101

Post by rektide »

ethbr0 wrote: post #95
foobarian wrote: post #88

Earlier quoted context omitted.

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 t…

Rocket engines require onboard oxidizer (or equivalent), so you have to carry a substantial additional amount of mass along with you. Air-breathing engines are able to save all that mass by using atmospheric oxygen. This matters, because it's the rocket equation in reverse: no onboard oxidizer = lighter vehicle = less fuel needed = even lighter vehicle = longer range / more payload

this is a good queue-in to start talking about mass ratio: the ratio of weight that is dedicated to payload versus the weight of the delivery platform and it's fuel (slightly simplified take).

this device is almost certainly air breathing. there's simply too big an oxygen-breathing-demand at speed to do anything else for sustained high speed flight, where you need to be generating a lot of motive force.

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

#102

Post by credit_guy »

nielsbot wrote: post #79
credit_guy wrote: post #24

Earlier quoted context omitted.

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"

Is this a lot? Missiles are quite expensive in general. $3.8 BN is not the budget for this single program, but for several, 8 per this source [1] (although, now it might be 1 or 2 less).

For this particular weapon, a somewhat similar weapon I can think of is the European Meteor [2], which is ramjet (rather than scramjet) powered, and reaches Mach 4, rather than over Mach 5 as this one is supposed to do. Meteor comes at a cool cost of EUR 2 MM per piece. Think about it, you fire one missile like that, and it's like destroying 10 Ferraris.

[1] https://www.flightglobal.com/flight-international/8-key-hype...

[2] https://en.wikipedia.org/wiki/Meteor_(missile)

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

#103

Post by SonicScrub »

sbierwagen wrote: post #99
SonicScrub wrote: post #90

Earlier quoted context omitted.

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 s…

>highest speeds only at altitudes where the atmosphere is more individual particles than a continuous gas (it's apogee of 62 miles [...] ) Isn't velocity lowest at apogee?

I misspoke a bit here. For an orbital vehicle, yes absolutely. Since this vehicle has a relatively shallow suborbital trajectory, I assumed the vehicle has a 1st burn to reach an apogee of ~100km. Upon reaching apogee it orientates itself towards it's earth-bound target, and then executes a second burn. Thus accelerating under thrust towards it's target. Ergo it's maximum speed would occur somewhere between it's apogee and when it re-enters the atmosphere. At least that was my interpretation of the text in the article.

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

#104

Post by addaon »

Armisael16 wrote: post #77
throwawaycuriou wrote: post #72

Earlier quoted context omitted.

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).

Nor the Falkland Islands, which is probably a more likely (although still unlikely) trouble spot.

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

#105

Post by micromacrofoot »

Uhh... is this NOT propaganda for the US Air Force? I'm always a little surprised when I see vaguely technical articles for US military equipment on the front page.

If you look up the publisher, Air Force Association, this is from their about page:

>Our mission is to promote dominant U.S. Air and Space Forces as the foundation of a strong National Defense; to honor and support our Airmen, Guardians, and their Families; and to remember and respect our enduring Heritage.

That statement alone doesn't pass the smell test for me. Am I being paranoid?

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

#106

Post by tkojames »

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,…

China is not going to nuke a carrier group sorry but that is insane. The second that happened say goodbye to entire world. There is reason we have boomer subs. One Ohio class sub could legitimately end the world.

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

#107

Post by tlear »

throwaway210222 wrote: post #40
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,…

> 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…

Nobody except Japan maybe UK and Australia is likely to do anything.

US itself is likely to turn tail and run if attack in not nuclear. Nuclear attack might inject some spine into response.

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

#108

Post by tptacek »

jasonwatkinspdx wrote: post #91
tptacek wrote: post #10

Earlier quoted context omitted.

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

Eh, you see a headline every so often alleging this but they're pretty far off the mark. CSGs are defended by the entire system operating in layers. During conflict conditions they'll have airborne early warning radar flying to see threats coming a long way out. There's usually at least 4 AEGIS equipped ships. The carrier air wing will be doing patrols and intercepting threats at great distance. The carrier itself wi…

Has the belief that these platforms are survivable ever been tested in a meaningful scenario (ie, a conflict between two carrier-group-capable adversaries)? I get that the Navy does a lot of stuff to mitigate this threat, but it's a hell of a threat to mitigate.

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

#109

Post by hindsightbias »

fnord77 wrote: post #94

would a MARV-tipped ICBM be able to reach a target faster than flying straight at it at Mach 5? I was looking for MARV reentry velocities, couldn't find any numbers. A regular ballistic missile hits mach 20+ on reentry but I don't know if it maintains that speed all the way to the target.

Marvs are just Mirvs that maneuver. They will go the same speed until they maneuver.

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

#110

Post by jcun4128 »

dragonwriter wrote: post #86
dd444fgdfg wrote: post #84

Earlier quoted context omitted.

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…

Would suck "starting over". Irradiated land, regression in progress with fallout.
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