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The Rise of Hypersonic Weapons

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Re: The Rise of Hypersonic Weapons

#101

Post by robryk »

drzaiusapelord wrote: post #87
robryk wrote: post #85

Earlier quoted context omitted.

> I'm not saying this isn't possible, but right now you'd have to fly an enemy drone or plane near the carrier group to get any targetting information and that would be shot down or jammed well before it could determine the exact locale (...) What about optical satellite observation?

My understanding is that its too slow and not accurate enough for pinpoint tracking of targets, assuming you can even find the carrier group in the vast ocean. This is why the military uses spotting planes, drones, gps, and laser instead of just shooting down coords via satellites. Also, in wartime there will probably be decoys and other counter-measures that might be hard to differentiate from satellite resolution.…

> My understanding is that its too slow and not accurate enough for pinpoint tracking of targets (...)

I find these two assertions very surpsising. Which part of the process do you expect to be slow and what do you mean by slow? Why do you expect accuracy much smaller than the size of a pixel in an image?

Re: The Rise of Hypersonic Weapons

#102

Post by georgeecollins »

theptip wrote: post #61
drzaiusapelord wrote: post #43

Earlier quoted context omitted.

Or nuclear tipped cruise missiles on ships or in-air bombers. The nuclear triad is still unbeatable. The article is pretty terrible in general. Hypersonics won't change the balance of anything, especially considering what a decent sized one can do. If you're delivering nuclear-levels of destruction with hypersonics then your opponent will retaliate with nuclear weapons. There will be no exception for "Oh, you used hy…

I think the nuclear angle is a red herring, and that the real destabilizing aspect of hypersonic weapons is that they can take out carriers, at much lower cost. The entire foundation of US force projection is built upon the carrier battle group. If putting your $5b carrier in the South China Sea makes it vulnerable to getting taken out by a $5m missile, then the balance of power has changed. Obviously there's nuclear…

$5 billion carrier? We wish. Try $13 billion. We're never going to put carriers in the South China Sea in a shooting war.

http://www.marketwatch.com/story/the-us-navys-new-13-billion...

Re: The Rise of Hypersonic Weapons

#103

Post by credit_guy »

ewr24 wrote: post #7

> However, hypersonic weapons do not need to be nuclear in order to be disruptive, as demonstrated by the United States’ focus on conventional hypersonic weapons. Does China and Russia believe that? It takes a few minutes to swap conventional and nuclear warheads. If anything US is the leader in this new cold war.

It's very difficult to see a scenario where it makes sense to put a nuclear warhead on a hypersonic missile. The fact is, hypersonic missiles are dog slow compared to ICBMs. ICBMs though suffer from the tyranny of the rocket equation (most of the fuel they burn is used to push the rest of the fuel), so the mass of the warhead is a small fraction of the total mass of the rocket (for Trident 2 it's about 7%). The main problem is that ICBM's have to carry their own oxydizer, which is heavy. Cruise missiles get oxygen from the air, and this is a big deal. For a Tomahawk the warhead is 35% of the total mass of the missile. Now when you deliver a nuclear warhead (or a bunch), you don't care that much about the ratio warhead/total mass, since nuclear carries a lot of punch in a small package. And if you plan to start WW3, you might as well do it quick, no reason to use a (relatively) slow delivery vehicle, like a hypersonic one, when you can use an ICBM.

It's when you want to deliver conventional explosives that you care about how big your rocket is. It's one thing for the rocket to be 3 times as big as the warhead (Tomahawk) and another to be 15 times as big (Trident 2). The Tomahawk is really slow though, so the idea of the hypersonic is to be faster, at the cost of having a smaller delivery ratio. The fastest current cruise missile, the Russian-Indian Brahmos has a 12% ratio of warhead to total mass (if launched from an airplane, less if launched from the ground), and a speed of about Mach 3. What would be the ratio for a hypersonic weapon? It shouldn't be less than 7% (otherwise you keep it "simple" and use the Trident 2 design) and it's unlikely it will be higher than the 12% of the Mach3 Brahmos-A missile. It will be somewhere in between, and most likely not that disruptive after all.

Re: The Rise of Hypersonic Weapons

#104

Post by chucksmash »

mikeash wrote: post #46
eternalban wrote: post #44

Earlier quoted context omitted.

ICBMs are held in mutual check by MAD. US enjoys conventional dominance due to ability to project conventional force anywhere. This capability is in part supported by the ability to effectively shield remote force projection platforms from conventional threats. (For atomic, see MAD.) HS conventional weapons can neutralize the defensive shields. This undermines the projection platforms. That would make US insecure. If…

I thought the main things allowing for MAD at this point were the ability of retaliatory ICBMs to launch quickly before incoming weapons destroy them, and the ability for ballistic missile submarines to survive a strike by being hidden, and thus retaliate at leisure. I don't see how hypersonic weapons change either of that. They're not any faster than a missile, so the response time isn't worse, and they don't do any…

A lot of the apparent ambiguity could be resolved by looking at the number of launches and their trajectories:

A) there are simultaneous launches against many different targets. Conventional or not, the enemy is trying to remove your ability to retaliate. The implication is clear.

B) Only a small number of weapons have been fired off at one or just a few targets. Even if the weapons inflict heavy casualties, your ability to retaliate remains intact.

Re: The Rise of Hypersonic Weapons

#105

Post by theptip »

georgeecollins wrote: post #102
theptip wrote: post #61

Earlier quoted context omitted.

I think the nuclear angle is a red herring, and that the real destabilizing aspect of hypersonic weapons is that they can take out carriers, at much lower cost. The entire foundation of US force projection is built upon the carrier battle group. If putting your $5b carrier in the South China Sea makes it vulnerable to getting taken out by a $5m missile, then the balance of power has changed. Obviously there's nuclear…

$5 billion carrier? We wish. Try $13 billion. We're never going to put carriers in the South China Sea in a shooting war. http://www.marketwatch.com/story/the-us-navys-new-13-billion...

I was basing the cost on the last couple that were commissioned, like https://en.wikipedia.org/wiki/USS_George_H.W._Bush.

But agree with your point, the calculus only gets worse as more eggs are put in the basket.

Re: The Rise of Hypersonic Weapons

#106

Post by theptip »

drzaiusapelord wrote: post #74
theptip wrote: post #61

Earlier quoted context omitted.

I think the nuclear angle is a red herring, and that the real destabilizing aspect of hypersonic weapons is that they can take out carriers, at much lower cost. The entire foundation of US force projection is built upon the carrier battle group. If putting your $5b carrier in the South China Sea makes it vulnerable to getting taken out by a $5m missile, then the balance of power has changed. Obviously there's nuclear…

I believe the common wisdom here is that no nation has remotely accurate targeting location on US carriers. This hypothetical attack would require intelligence and sensing capabilities that don't currently exist. I'm not saying this isn't possible, but right now you'd have to fly an enemy drone or plane near the carrier group to get any accurate targeting information and that plane would be shot down or jammed well b…

I hadn't heard that point about carriers being hard to track down before, do you have any good links for further reading?

If the point about China/Russia increasing their relative punching power vs. the US doesn't feel significantly to you, what about when they are sold on the open market to any country that wants one? Any country in the world being able to take out a carrier would change the way that power is projected in a very big way. Suddenly attack and defense are much more asymmetrical, which favours the small actors (this would work against Russia and China too, but they have less to lose than the US does in this regard).

Re: The Rise of Hypersonic Weapons

#107

Post by ekianjo »

ChuckMcM wrote: post #86
ekianjo wrote: post #26

> would be able to knock out a target’s nuclear capabilities fast enough and thoroughly enough to pre-empt any attempt at a retaliatory strike. Did the author completely forget about nuclear subs?

I believe the author was implying countries like North Korea or Iran who might develop a nuclear warhead and possibly ICBM technology but not have the other options (air or sea launch). That said, a sub at missile launch depth is susceptible to a hypersonic weapon from above. With sufficient mass, even a kinetic only impact from the surface could take out those subs. A nuclear depth charge can take out subs down to t…

> That said, a sub at missile launch depth is susceptible to a hypersonic weapon from above

The point of subs is that you don't know where they are. That's why we have them in the first place.

Re: The Rise of Hypersonic Weapons

#108

Post by ekianjo »

mikeash wrote: post #70
jessriedel wrote: post #60

Earlier quoted context omitted.

> or in-air bombers. It's no longer the case that the US and Russia maintain nuclear bombers in air continuous.

It hasn't been for a long time, too. The US discontinued continuous air alert in 1968, when it became apparent that it was just too risky (planes kept crashing with live weapons on board) and ICBMs and SLBMs made it unnecessary. I'm sure it could be restarted now if it looked to be necessary, but it doesn't seem to be.

> It hasn't been for a long time, too

If my memory does not fail me, the book COmmand Control claims that it did continue until well in the 90s.

Re: The Rise of Hypersonic Weapons

#109

Post by sliken »

LoSboccacc wrote: post #20

I think this article conveniently forgets to mention nothing hypersonic of sort will outrun lasers. lasers can't track of course and range is limited by factor like atmosphere and earth curve, but still, thinking about an hypothetical future scenario hypersonic weapons would just get lasered down by automated point defences all the same as conventional speed ordinance.

Typical airplanes and missles have very thin skins, often of aluminum or titanium. Fairly easy to track, fairly easy to puncture. You also have time to carefully track, deploy, and fire.

Problem with hypervelocity weapons is that they have to be heavily armored and cooled just to survive the onslaught of air at mach 5 and above. You also are surrounded by a hot dense plasma, so much so that radios can't get through it.

So the power, tracking, accuracy, and compensation for radical differences in air pressure, air temperature, and related just to get to the surface which is radically stronger than your average airplane or missle.

Also note that there doesn't even necessarily need to be a big easy to set of bomb on said missle. Even a pure kinetic weapon can be pretty effective at mach 5 and up.

So certainly not impossible, but not going to be practical for awhile.

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