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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

#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, I suppose it makes sense to be one step ahead of where the game is going.

Or is there something more to this?

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

#13
post #11

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?

I think there might be a grammar problem in your statement. What did you mean?

He means how fast does a missile need to go so that the kinetic energy is greater than the chemical/explosive energy.

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

#14
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,…

I imagine the use case is more conventional weapons, for example taking out a navy flagship.

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

#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.

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

#17
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,…

Better we try to one up each other with fast cruise missiles than with more nukes.

In fact, nukes are useless now, let's just get rid of all of them. (wink wink)

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

#18

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?

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, coupled with a chemical warhead, to hit hardened targets

Source:

https://en.wikipedia.org/wiki/Orders_of_magnitude_(energy)

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

#19
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.

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.

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

#20
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.

>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.

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