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U.S. Air Force says it conducted successful hypersonic weapon test

reuters.com

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Re: U.S. Air Force says it conducted successful hypersonic weapon test

#41

Post by moron4hire »

booi wrote: post #34
bparsons wrote: post #22

Earlier quoted context omitted.

The Pentagon does this every decade. They constantly need some sort of existential threat to respond to in order to justify budget increases.

What's the defense against a hypersonic missile then? Current Aegis and CIWS defensive tech will not hit something traveling that fast. Surely the Pentagon doesn't even need to justify budget increases when we give them more budget than they ask for every year regardless.

They have to know what to hit and make sure the target they are tracking is actually a real target.

Re: U.S. Air Force says it conducted successful hypersonic weapon test

#42

Post by riku_iki »

rootusrootus wrote: post #3
ortusdux wrote: post #2

It was an AGM-183 ARRW. The test on the 14th hit Mach 5, but they claim a theoretical top speed of Mach 20. https://en.wikipedia.org/wiki/AGM-183_ARRW

Reading through the timeline on that page, it sounds like Congress has decided to kill the project. I wonder if this successful test will turn that around.

It says they transferred half of funds from procurement to R&D, probably because previous tests failures.

Re: U.S. Air Force says it conducted successful hypersonic weapon test

#43

Post by [deleted] »

robonerd wrote: post #26
ramesh31 wrote: post #24

Earlier quoted context omitted.

>All ballistic missile reentry vehicles are hypersonic too Sure, but ballistic trajectories are trivially interceptible. It's not just about speed. The new arms race is with hypersonic glide vehicles that are capable of maneuvering all the way to the target at mach 8+. With that, the weapon becomes impossible to intercept with any existing technology.

My money is still on Aegis BMD intercepting the missile during the terminal phase. Hypersonic glide-boost weapons are mainly for avoiding mid-course interception. When you're going hypersonic, 'maneuverable' is relative; the turning radius is quite huge and such missiles will be easy for Aegis to track during the terminal phase.

[deleted]

Re: U.S. Air Force says it conducted successful hypersonic weapon test

#44

Post by robonerd »

booi wrote: post #34
bparsons wrote: post #22

Earlier quoted context omitted.

The Pentagon does this every decade. They constantly need some sort of existential threat to respond to in order to justify budget increases.

What's the defense against a hypersonic missile then? Current Aegis and CIWS defensive tech will not hit something traveling that fast. Surely the Pentagon doesn't even need to justify budget increases when we give them more budget than they ask for every year regardless.

> Current Aegis and CIWS defensive tech will not hit something traveling that fast.

Aegis BDM is designed to hit hypersonic reentry vehicles. CIWS is irrelevant, why even bring it up?

Re: U.S. Air Force says it conducted successful hypersonic weapon test

#45

Post by rib3ye »

nathanyz wrote: post #7

Probably just us flexing that we have them too. Likely have had them, but kept it quiet as no need to declare our capabilities. Since others are crowing about it, just letting them know we also have same.

Yes, but only because our Congress is trying to make political theater of the topic.

https://www.youtube.com/watch?v=qz_2r6rWgY8

Re: U.S. Air Force says it conducted successful hypersonic weapon test

#46

Post by throwaway0a5e »

ramesh31 wrote: post #38
robonerd wrote: post #26

Earlier quoted context omitted.

My money is still on Aegis BMD intercepting the missile during the terminal phase. Hypersonic glide-boost weapons are mainly for avoiding mid-course interception. When you're going hypersonic, 'maneuverable' is relative; the turning radius is quite huge and such missiles will be easy for Aegis to track during the terminal phase.

>When you're going hypersonic, 'maneuverable' is relative; the turning radius is quite huge and such missiles will be easy for Aegis to track during the terminal phase. Except the associated plasma shielding makes it invisible to radar. And the Russian ones are capable of sea skimming and maneuvering at mach 8 in the terminal phase. At those speeds, you're talking horizon to impact in seconds. We really have nothing…

>Except the associated plasma shielding makes it invisible to radar.

Anything moving mach 8 is gonna light up like a Christmas tree in other parts of the EM spectrum.

Re: U.S. Air Force says it conducted successful hypersonic weapon test

#47

Post by Victerius »

dirtyid wrote: post #40
cersa8 wrote: post #10

How much of this is hype and boasting about military advances. According to this article hypersonic missiles are far from practical https://www.scientificamerican.com/article/the-physics-and-h...

Not practical for US who has platforms to hit global targets at much lower costs, i.e. money spent on hypersonic research can build up enough JASSMs to last until WW5. But IMO useful backup if adversaries manage to negate platforms like carriers and long range bombers. Basically, establishing conventional MAD with CONUS Prompt Global Strike using icbm/hypersonics. Flip side is this is massively benefitial to PRC (or…

> build up enough JASSMs to last until WW5

Love the imagery.

Re: U.S. Air Force says it conducted successful hypersonic weapon test

#48

Post by kcb »

staunch wrote: post #12

My understanding is that Russia and China are building hypersonic glide missile so they can penetrate any US missile defense system, which the US doesn't really even have. And neither does Russia or China have an effective missile defense system that the US needs the capability to defeat. So it seems like an arms race without either side really having advanced to the point of necessitating a further step. Then again,…

> US missile defense system, which the US doesn't really even have

Uh..Missile defense is a massive part of US Navy doctrine and is pretty much the primary purpose of every Destroyer, Cruiser, and soon Frigate in the Navy at this point.

Without a doubt, the Aegis system and THAAD are the direct reason for these developments from China and Russia.

Re: U.S. Air Force says it conducted successful hypersonic weapon test

#49

Post by zmgsabst »

theptip wrote: post #36
zmgsabst wrote: post #18

Earlier quoted context omitted.

Not really. Even for hypersonics, the efficiency of chemicals at storing energy and then releasing it is hard to beat. 1 kg of TNT produces 4.2MJ; to get the same energy in 1kg of projectile you’d need to travel at ~6500 miles per hour. (About mach 9 at sea level.) The role of hypersonics is in application: - sudden attacks, to prevent response - low altitude, high velocity attacks, to defeat intercept - penetration,…

Appreciate the detail. I'm not sure I see the conclusion as obvious though; if a 2kg weapon is going Mach 20 (as the weapon in the OP apparently does), with 1kg of that being TNT, then the explosives only provided 20% of the energy (rounding to the nearest 10% to make the example clearer). If you just lobbed the same 1kg weapon at Mach 20 then you'd have halved the weight, and reduced the energy to 40%. Presumably lo…

Per OP:

> The U.S. Air Force said on Monday it had conducted a successful test of a hypersonic weapon, which flew at five times the speed of sound.

But to your question:

> around Mach 10-20 is where the tradeoff could become non-obvious, depending on how much you value weighing less?

The same logic holds at mach 5-8 (ie current hypersonics), which is why they’re being developed:

You want a weapon that can surprise, evade, or penetrate better — even if that’s less destructive overall.

Re: U.S. Air Force says it conducted successful hypersonic weapon test

#50

Post by hdjjhhvvhga »

robonerd wrote: post #26
ramesh31 wrote: post #24

Earlier quoted context omitted.

>All ballistic missile reentry vehicles are hypersonic too Sure, but ballistic trajectories are trivially interceptible. It's not just about speed. The new arms race is with hypersonic glide vehicles that are capable of maneuvering all the way to the target at mach 8+. With that, the weapon becomes impossible to intercept with any existing technology.

My money is still on Aegis BMD intercepting the missile during the terminal phase. Hypersonic glide-boost weapons are mainly for avoiding mid-course interception. When you're going hypersonic, 'maneuverable' is relative; the turning radius is quite huge and such missiles will be easy for Aegis to track during the terminal phase.

Moreover, even if Aegis fails to intercept it, the manoeuvre to avoid the intercepting missiles in the terminal phase at hypersonic speeds means a huge miss, at least for conventional warheads.
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