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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

#31

Post by coding123 »

Buttons840 wrote: post #17
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,…

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)

Nukes simply existing may have saved more lives at this point. That could, of course, change in seconds at any time.

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

#32

Post by tmccrary55 »

ramesh31 wrote: post #24
robonerd wrote: post #19

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.

If only someone had directed energy weapons...

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

#33

Post by secondcoming »

zozin wrote: post #16
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...

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.

I'm no expert, but I think one of the issues with the missiles from the 60's was that they got so hot from air friction that a plasma enveloped it which prevented it from being guided. Same as how comms are temporarily lost with space shuttles on re-entry. Maybe the Russians have overcome that issue.

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

#34

Post by booi »

bparsons wrote: post #22
ramesh31 wrote: post #20

Earlier quoted context omitted.

>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.

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.

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

#35

Post by MR4D »

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...

I'd love to pick this article apart, but instead I'll just offer this:

The Phoenix missile (which used to be carried by the F-14) is borderline hypersonic [0]. And it is shot at airplanes.

Now imagine an Exocet-type missile but at a much higher speed.

A fast missile does one very important thing - it reduces the time the defender has to react, and thereby increases the odds of the attack succeeding. Glide-paths, targeting, etc are just variations of an attack plan - speed is what kills.

[0] - https://en.wikipedia.org/wiki/AIM-54_Phoenix#:~:text=Speed%3...

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

#36

Post by theptip »

zmgsabst wrote: post #18
oneoff786 wrote: post #4

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,…

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 lower weight means easier to maneuver (more agile for intercepting or avoiding countermeasures, depending on what you're trying to hit).

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

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

#37

Post by manachar »

Buttons840 wrote: post #17
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,…

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)

You joke about nukes, but since they're such an "unthinkable" weapon they've become almost useless for most people who have them. You need them so that others with fewer compunctions are not able to steamroll you, but as an actual help to the kinds of conflicts currently going on and likely to happen in the future, they're just not as effective.

Whether that's fast cruise missiles, more powerful drones, more disposable drones, robot warriors, cyber-warfare, etc. militaries are trying to find the technology that breaks the stalemate caused by MADD.

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

#38

Post by ramesh31 »

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.

>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 that can touch it.

https://en.wikipedia.org/wiki/3M22_Zircon

We like to think of ourselves as massively advanced beyond Russia and China, and we are to an extent. But the reality is that the US military has wasted the last 20 years in pointless counterinsurgency operations that have narrowed our view to the actual threats we face, and de-prioritized this kind of cutting edge stuff. There's some serious catching up we'll need to do (both technologically and organizationally) to maintain deterrence against the rising conventional threats of authoritarian major powers.

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

#39

Post by hungryforcodes »

ramesh31 wrote: post #20
zozin wrote: 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.

They have already denied the US the South China Sea -- just by expanding their economy. The US is a joke here. China -- for example -- in the last 20 years has started more than 400 companies in the Philipenes at least and where else? Structural changes to the economy, basically. While Europe and the US persist in this 1970s: "we will give the primitives subsidies and cash prizes" -- demonstrating that they are totally out of touch with the region. Colonialism is over. These countries have money. China is actually installing economic zones and other structures which give them direct control over the region. Aircraft Carrier Groups are no match for this.

I'm not saying I like or dislike it. But its incrediably evident if you live in the region.

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

#40

Post by dirtyid »

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 anyone else) who can't catchup in conventional force posture to hit CONUS with anything but hypersonics. For them it's low hanging asymmetric fruit that comprehensively deters US power projection. IMO we're entering era where advanced rocketry including meter level CEP and accurate terminal guidance will proliferate and obviate a lot advantages of current power projection platforms.

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