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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

#71

Post by robonerd »

michael1999 wrote: post #28
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?

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

> de-orbiting tungsten rods

Over-hyped I think. Sure the kinetic energy is incredible, but what of the terminal ballistics? I think these would have substantial over-penetration against anything except deep bunkers; most of that kinetic energy would be spent driving that rod through bedrock, like an APFSDS dart shot into tank armor. Good for punching holes in things.

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

#72

Post by steve76 »

hungryforcodes wrote: post #39
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.

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 total…

No post body was provided.

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

#73

Post by greedo »

nimbius wrote: post #66
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.

the missile in TFA only achieved fivefold the speed of sound. Russias Avangard moves at twenty-seven times the speed of sound. thats faster than the re-entry speed for the space shuttle endeavor. it also advertises a newfound maneuverability. Americans under-estimate their adversaries sadly quite often. when the TU95 bear first arrived during the cold war era its specifications were habitually lowballed by analysts u…

The US also overestimates the threats from its potential adversaries quite frequently. The Soviets weren't 10ft tall, and the modern Russian military has been shown to be quite fragile in Ukraine. Perhaps military intelligence is a bit harder than posting on HN.

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

#74

Post by greedo »

hdjjhhvvhga wrote: post #50
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.

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.

I don't know of any missiles that have enough situational awareness to attempt to actively avoid an interceptor. They might dispense decoys (like the Iskander does), but a hypersonic cruise missile won't have the appropriate radar to detect an incoming interceptor. It might have an ECM/ECCM package that can tell when it's being targeted by a radar system, but that's about it.

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

#75

Post by hammock »

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?

Look up "rods from God."

https://en.wikipedia.org/wiki/Kinetic_bombardment

https://www.businessinsider.com/air-force-rods-from-god-kine....

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

#76

Post by greedo »

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.

Bah...

A SLBM (sub-launched ballistic missile) can reach a coastal target in less than five minutes depending on the exact trajectory. Good luck trying to intercept that.

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

#77

Post by towaway15463 »

Aunche wrote: post #58
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.

Iron dome can't even intercept all of the subsonic rockets fired by terrorists with very limited budgets. Even if the entire US GDP was directed towards missile defense, I doubt that China or Russia would have any trouble overwhelming these systems simply by throwing enough conventional MIRVs at it.

Being able to ensure a strike with a single missile is a force multiplier especially when it comes to deterrence. If you need 10 missiles to ensure one hit your enemy may think they have favourable odds in a first strike. If you only need 1 missile per hit then the outcome of a first strike is not so good if they don’t get every single one of your missiles.

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

#79

Post by michael1999 »

robonerd wrote: post #71
michael1999 wrote: post #28

Earlier quoted context omitted.

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

> de-orbiting tungsten rods Over-hyped I think. Sure the kinetic energy is incredible, but what of the terminal ballistics? I think these would have substantial over-penetration against anything except deep bunkers; most of that kinetic energy would be spent driving that rod through bedrock, like an APFSDS dart shot into tank armor. Good for punching holes in things.

Completely agree. Those systems solve a bunch of non-problems and completely destabilize MAD. There's a reason they were never developed.

But I wouldn't discount to the ability of weapons designers to figure out the frangibility and deliver the bulk of the energy to a tuneable depth.

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

#80

Post by sudosysgen »

thereddaikon wrote: post #52
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.

The Russian "hypersonic" missile is just the upper stage of a short ranged ballistic missile launched from an aircraft. Its just an existing weapon with more steps. The Chinese hypersonic weapons everyone is worried about is a boost glide vehicle. Basically a ballistic missile with a hypersonic lifting body as its warhead as opposed to a blunt body RV you usually see. This makes it more maneuverable and potentially h…

Russia also has an air-breathing hypersonic missile with a scramjet engine - 3M22 Zircon. It is being field-tested and is already starting production after more than a dozen successful tests including hitting moving target - making them much further in development than HAWC which only recently managed to fly for any distance without blowing up and never actually struck a target.

So your impression is not correct. The Russians and the Chinese actually are much further along for all classes of hypersonic missiles.

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