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US hypersonic missile fails in test- 2nd consecutive failed attempt

bloomberg.com

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Re: US hypersonic missile fails in test- 2nd consecutive failed attempt

#31

Post by bilsbie »

superkuh wrote: post #14
edenceover wrote: post #5

Given that the bomber gap, missile gap and the cruiser gap was all shown to be fictional, I do wonder if the perceived hypersonic gap is real.

Correct. No one has "real" hypersonic missiles that travel in the atmosphere for extended periods(*1). The heating problems for shock impingment in non-"simple conicals" has *not* been overcome and won't be. "Hypersonic" missiles are mostly just ICBMs with a very brief passage through the dense lower atmosphere where there's enough lift. And if they try to go higher up to escape the heat flux there's not enough for l…

What about scram jets though?

Re: US hypersonic missile fails in test- 2nd consecutive failed attempt

#32

Post by danbruc »

bufferoverflow wrote: post #30
superkuh wrote: post #14

Earlier quoted context omitted.

Correct. No one has "real" hypersonic missiles that travel in the atmosphere for extended periods(*1). The heating problems for shock impingment in non-"simple conicals" has *not* been overcome and won't be. "Hypersonic" missiles are mostly just ICBMs with a very brief passage through the dense lower atmosphere where there's enough lift. And if they try to go higher up to escape the heat flux there's not enough for l…

"Sprint accelerated at 100 g, reaching a speed of Mach 10 (12,300 km/h; 7,610 mph) in 5 seconds. Such a high velocity at relatively low altitudes created skin temperatures up to 6,200 °F (3,430 °C)" This is in 1975.

But sprint did not have an airbreathing engine and was intended for close range interception and not long range missions.

Re: US hypersonic missile fails in test- 2nd consecutive failed attempt

#33

Post by jjoonathan »

bufferoverflow wrote: post #30
superkuh wrote: post #14

Earlier quoted context omitted.

Correct. No one has "real" hypersonic missiles that travel in the atmosphere for extended periods(*1). The heating problems for shock impingment in non-"simple conicals" has *not* been overcome and won't be. "Hypersonic" missiles are mostly just ICBMs with a very brief passage through the dense lower atmosphere where there's enough lift. And if they try to go higher up to escape the heat flux there's not enough for l…

"Sprint accelerated at 100 g, reaching a speed of Mach 10 (12,300 km/h; 7,610 mph) in 5 seconds. Such a high velocity at relatively low altitudes created skin temperatures up to 6,200 °F (3,430 °C)" This is in 1975.

https://www.youtube.com/watch?v=YZZV464z9g8

That's a pretty fast missile...

(RV zips by at 3x the speed)

Re: US hypersonic missile fails in test- 2nd consecutive failed attempt

#35

Post by iamtheworstdev »

bilsbie wrote: post #31
superkuh wrote: post #14

Earlier quoted context omitted.

Correct. No one has "real" hypersonic missiles that travel in the atmosphere for extended periods(*1). The heating problems for shock impingment in non-"simple conicals" has *not* been overcome and won't be. "Hypersonic" missiles are mostly just ICBMs with a very brief passage through the dense lower atmosphere where there's enough lift. And if they try to go higher up to escape the heat flux there's not enough for l…

What about scram jets though?

they have to go high for reasons mentioned in parent. Their launch altitude is normally 40,000ft to begin with. then they climb from there.

Re: US hypersonic missile fails in test- 2nd consecutive failed attempt

#38

Post by newaccount2021 »

edouard-harris wrote: post #12
edenceover wrote: post #5

Given that the bomber gap, missile gap and the cruiser gap was all shown to be fictional, I do wonder if the perceived hypersonic gap is real.

That's a very reasonable question, though in cases like these it seems prudent to err on the side of being too paranoid rather than the opposite.

but this is gobs of money that could be much better spent by the military

just off the top of my head:

- dramatic improvements in military IT (search for recent story "just give us new computers")

- more investments in unmanned combat systems

- just buy more of the things that work...numbers matter

etc etc

Re: US hypersonic missile fails in test- 2nd consecutive failed attempt

#40

Post by mannykannot »

ren_engineer wrote: post #6

both test failures seem to have been during the booster rocket phase and they weren't even able to test or collect data on the missile component Lockheed is in charge of development, just like the SLS program. I'm curious how hard it would be to have SpaceX make an attempt or if they would even be willing. Seems safe to say they know rockets far better than Lockheed

This article describes the first test as ending in a booster failure, but describes the problem here as the failure of the test asset to ignite. I would guess that the test asset is the hypersonic device itself.
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