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

reuters.com

21–30 of 131 posts

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

#21
post #8
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

Mach 20 is so fast. It's around the Earth at the equator (ground level) in two hours.

Orbital speeds within the atmosphere, basically.

Edit: I suppose that means the vehicle wouldn't need any aerodynamic lift when going at full speed; indeed, to maintain altitude it'd need negative lift.

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

#22
post #16

Earlier quoted context omitted.

They are. Chinese and Russian “advances” in hypersonics are pure marketing. The US was testing scramjets in the 1960s. The US has a hypersonic space plane. Alas, the media fell for it and billions are now being spent on “catching up” with our “peer” competitors.

>Alas, the media fell for it and billions are now being spent on “catching up” with our “peer” competitors. These things are no joke. I felt the same before actually looking into it. China can effectively deny the South China Sea to our carrier fleets with their land based hypersonic weapons. There is absolutely no means of intercepting them with current technology.

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

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

#23
post #16
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...

They are. Chinese and Russian “advances” in hypersonics are pure marketing. The US was testing scramjets in the 1960s. The US has a hypersonic space plane. Alas, the media fell for it and billions are now being spent on “catching up” with our “peer” competitors.

the perfect cover for funneling money into Metal Gear

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

#24
post #16

Earlier quoted context omitted.

They are. Chinese and Russian “advances” in hypersonics are pure marketing. The US was testing scramjets in the 1960s. The US has a hypersonic space plane. Alas, the media fell for it and billions are now being spent on “catching up” with our “peer” competitors.

All ballistic missile reentry vehicles are hypersonic too. Talk of "hypersonic" without specifying the technology and actual capabilities is quite silly. Presumably hypersonic cruise missiles is implicit context.. but I don't believe the general public understands that and the media is doing a generally terrible job of communicating it.

>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.

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

#25

Earlier quoted context omitted.

All ballistic missile reentry vehicles are hypersonic too. Talk of "hypersonic" without specifying the technology and actual capabilities is quite silly. Presumably hypersonic cruise missiles is implicit context.. but I don't believe the general public understands that and the media is doing a generally terrible job of communicating it.

>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.

Existing. Soon to be found.

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

#26

Earlier quoted context omitted.

All ballistic missile reentry vehicles are hypersonic too. Talk of "hypersonic" without specifying the technology and actual capabilities is quite silly. Presumably hypersonic cruise missiles is implicit context.. but I don't believe the general public understands that and the media is doing a generally terrible job of communicating it.

>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.

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

#27

>> "Following separation from the aircraft, the ARRW's booster ignited and burned for expected duration, achieving hypersonic speeds five times greater than the speed of sound," it said. Big deal. The booster is just a rocket. And Mach numbers are meaningless without altitude reference. Anything that travels to the outer atmosphere/space will hit extreme Mach numbers on the way up/down. So without any further data th…

The ARRW boost-glide vehicle is unpowered, but maneuverable. This test used a dummy boost-glide vehicle, though. They haven't disclosed if releasing the dummy vehicle was part of this test, and if so whether it succeeded. This test was just testing the boost phase.

edit: From the Lockheed Martin press release (https://news.lockheedmartin.com/2022-05-17-us-air-force-and-...):

> The successful flight demonstrates the weapon’s ability to reach and withstand operational hypersonic speeds, collect crucial data for use in further flight tests, and validate safe separation from the aircraft to deliver the glide body and warhead to designated targets from significant standoff distances. … Additional booster and all-up-round test flights will continue throughout 2022, before reaching Early Operational Capability (EOC) in 2023.

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

#28

I believe most explosives detonate in the air anymore. Is there a speed threshold where the kinetic energy is enough to justify not doing that?

Many anti-air missiles detonate at range and destroy with shrapnel. And shrapnel damage is just kinetic. But that's probably not what you mean.

Yes. For lightly armoured targets, their own velocity might do it. See https://en.wikipedia.org/wiki/Brilliant_Pebbles#Brilliant_Pe...

And if you want to go further, de-orbiting tungsten rods make the explosives redundant. https://en.wikipedia.org/wiki/Kinetic_bombardment

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

#29
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.

From Lockheed's press release:

Additional booster and all-up-round test flights will continue throughout 2022, before reaching Early Operational Capability (EOC) in 2023.

So it sounds like they found the cash somewhere.

https://news.lockheedmartin.com/2022-05-17-us-air-force-and-...

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

#30
post #8

Earlier quoted context omitted.

Mach 20 is so fast. It's around the Earth at the equator (ground level) in two hours.

Orbital speeds within the atmosphere, basically. Edit: I suppose that means the vehicle wouldn't need any aerodynamic lift when going at full speed; indeed, to maintain altitude it'd need negative lift.

Barely within the atmosphere, I assume. Mach 20 at commercial jet altitudes would probably melt the aircraft.
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