Hypersonic HAWC missile flies, but details are kept hidden

https://www.airforcemag.com/hypersonic-hawc-missile-flies-details-kept-hidden/

by mzs • 5 years ago

95 182 5 years ago

echelon3• 5 years ago

As I understand it, China has hypersonic missiles and nukes, whereas the US does not.

Should a conflict in the South China sea break out, China could nuke US carrier groups assuming their satellites aren't taken out first. That spells game over for US projection of power if successful.

China could deploy air and submersible drones to get around downed satellites, but these have the potential of being jammed with EMP, other drones, etc. It could become a game of cat and mouse, and if the carriers get close enough, China's land-based missile defenses are toast.

Is the US developing hypersonics for close combat? How does this fit into a South China sea conflict, or does this assume the battle is closer to home? (If China goes blue water, is this meant to combat their carriers?)

If, when, and where will the theater be? What will the outcome be?

Would the conflict be limited to the coastal regions, or would it spill over into nuclear MAD?

Will either side back down?

I'm super curious about all of this, and I'm interested in more sources to follow. I don't know enough to understand military/navy Twitter.

masterof02• 5 years ago

What will the outcome be? Judging by what we did in Afghanistan, not good. I hope we don't send thousands to die and/or kill other people. If they invade the US, we fight, otherwise, we shouldn't be policing the world. I don't see the benefits of a war with China, or any other country at all.

emaginniss• 5 years ago

What if they decide they want to gobble up Taiwan, Vietnam, Japan, Australia, etc? Should we just sit back and say "it's not us, so this is fine?"

mrlonglong• 5 years ago

On the other hand, if China was to adopt the Taiwainese constitution and embrace democracy then yes, they could reunify.

newaccount2021• 5 years ago

there is no chance a US carrier could be nuked without a proportional response

justicezyx2• 5 years ago

The hypersonic missle won't carry nuclear war head. The impact is enough to render a CV lose combat capability. The modern weaponry are delicate machines. A 50s computer might withstand an earthquake. The modern one probably won't survive a drop less than 1 meter.

mzs2• 5 years ago

DF-17 + DF-ZF & Xingkong-2

https://gjia.georgetown.edu/2021/01/27/chinas-hypersonic-wea...

3pt141592• 5 years ago

Follow Arms Control Wonk. There's a bunch of OSINT folks in the podcast slack channel including friends of mine that have been interviewed by magazines like The Economist.

I'm there more for the cyberwarfare takes, but from what I understand nobody is seriously worried about a power imbalance between China and America regarding missile speed since interceptors aren't accurate enough, but that's just me regurgitating what I see tweeted around and talked about.

Edit: And don't be intimidated by people reverse engineering sidewinders in the Slack. The community is very open to humble, curious newcomers. They'll teach you how to analyze satellite imagery for free, haha.

justicezyx2• 5 years ago

https://openosint.slack.com/?redir=%2Fmessages%2Fosint%2F

This one?

PerkinWarwick• 5 years ago

Generally, I'd say that anti-carrier strike group tactics involve simply (well, maybe not so simple) overwhelming the defenses. Quantity can work as well as quality.

You might look into Russian missile work. Of course, as a land power (and not as invested in trade as China), their answers are different.

sudosysgen15• 5 years ago

The answers of China and Russia are pretty similar. Use air power or submarines to locate the carrier, fire hypersonic missiles.

tptacek2• 5 years ago

Is the premise here that carrier groups would be survivable in the absence of hypersonic missiles? They... aren't at all, are they?

WrtCdEvrydy• 5 years ago

Carrier groups are supposedly survivable except for the stealth subs and hypersonic missiles but noone has tested that theory.

I wonder if the future will be just a cheap ship with a large number of single-use missile launchers.

Enginerrrd• 5 years ago

Yes, no, maybe?

As far as I know, with existing known technology and defenses, there's probably a number n, such that if you launch more than n simultaneous non-hypersonic cruise missiles, an aircraft carrier is going to be unable to deal with them all. This of course assumes you can launch that many missiles, in range of the carrier, simultaneously, without advanced warning.

Now, the navy also isn't dumb, so I'd venture to guess they avoid parking their carriers within that range when possible, and that they probably have some other defenses like C-130's and other ships mounted with directed energy weapons and other missile defense and whatnot. I imagine they also aggressively pursue and maintain intelligence on the location, number, and readiness state of those missiles. This starts to get complicated because there's a complicated interplay of strategy and tactics related to the off-ship capabilities, and defenses have counter-strategies (such as launching a bunch of Surface-to-air missiles at those C-130's immediately prior to launching the cruise missles) and those counter-strategies have counter-strategies, etc. etc.

I also have no idea what that number n is. It could be infeasibly high.

krisoft2• 5 years ago

Every time the navy is asked about the survivability of the carrier groups they seem to start talking about the “whole kill-chain” of the enemy weapons. It sounds like they plan to knock out the targeting satelites before they could target them instead of trying to catch the missiles. Or at least thats how I read the tea leaves.

jasonwatkinspdx2• 5 years ago

Eh, you see a headline every so often alleging this but they're pretty far off the mark.

CSGs are defended by the entire system operating in layers. During conflict conditions they'll have airborne early warning radar flying to see threats coming a long way out. There's usually at least 4 AEGIS equipped ships. The carrier air wing will be doing patrols and intercepting threats at great distance. The carrier itself will be practicing emissions control and hiding within the sizable perimeter created by all of the above. And there's a lot of sophisticated EW decoys and such, that we don't know much about from open sources other than they're taken very seriously.

There's plenty of room for debate about just how effective this all is against a nation like China that has a lot of satellite intelligence/surveillance assets, but the simplistic "carriers have no defense" articles are just empty clickbait. These articles usually assert that there's no defense whatsoever against ballistic missiles, which ignores that 2 of those 4 AEGIS ships will be specialized to do exactly that, and have demonstrated it in testing.

One interesting tidbit is a few years back the US Navy submitted a request to do an exercise where they'd demonstrate taking down an inbound salvo of several 100 missiles simultaneously. Congress declined to allocate the budget for it.

Military planners certainly aren't omniscient or infallible, but they're a lot more sophisticated than the content free contrarian takes you see thrown around on the internet a lot. It ends up being a doomsayer about military technology is a pretty easy grift as nationalists on various sides drink it up uncritically and people with authoritative knowledge on the topic are constrained from openly rebutting it. All that said you do see some pretty in depth open info from GAO reports, stuff from CSBA, etc.

dragonwriter2• 5 years ago

Should a conflict in the South China sea break out, China could nuke US carrier groups

If China wants to start a nuclear exchange, sure. The US probably wouldn't go nuclear in response to an invasion of Taiwan, but it absolutely would in response to a nuclear attack on US forces.

bb101• 5 years ago

And our reality would segue into the storyline of Threads. The 1984 BBC film should be mandatory viewing for all people in positions of power. The bombing is only the start of the horror. https://www.youtube.com/watch?v=vgT4Y30DkaA

willvarfar• 5 years ago

Somewhat related to a China tech angle, I submitted this article about what Chinese stealth boats look like to the newest commercial radar satellites: https://news.ycombinator.com/item?id=28686121

numpad0• 5 years ago

Is that a big deal? Internet told me the reason why ships go only halfway YF-117 is because surface radar expects sea clutters, and an awkward black patch created by stealth features gives out its position and nature.

sudosysgen15• 5 years ago

... From the top. That is, the exact angle from which stealth doesn't matter.

throwaway2102222• 5 years ago

China could nuke US carrier groups assuming their satellites aren't taken out first. That spells game over for US projection of power if successful.

Incorrect, the USA will probably just shrug, and call in the other 11 super-carriers and 9 amphibious assault ships.

At the same time they will invoke NATO article 5 and a few other Asian mutual-defence treaties. 2 UK, 1 Spanish, 1 French, and 2 Italian carriers will arrive soon afterwards.

As will 4 Japanese, 3 French, 2 Australian and 2 South Korean helicopter carriers.

The trick isn't to take out one aircraft carrier: its to to be able to take them all out.

Armisael162• 5 years ago

Article 5 only applies to attacks in Europe or North America. The SCS is definitely in neither.

simonh• 5 years ago

That’s absolutely right if course. Taking out a carrier group, or even several carrier groups is if course doable, but by itself it isn’t an objective. It’s a means to an end, so without a strategic context it doesn’t mean anything.

echelon3• 5 years ago

The trick isn't to take out one aircraft carrier: its to to be able to take them all out.

Hypersonic missiles and nukes cost a lot less than a carrier. Assuming their surveillance doesn't get taken out, they can spam missiles.

China will have to have good signals intelligence for this to work, though.

tlear• 5 years ago

Nobody except Japan maybe UK and Australia is likely to do anything.

US itself is likely to turn tail and run if attack in not nuclear. Nuclear attack might inject some spine into response.

marstall• 5 years ago

I've read its actually very hard to find an aircraft carrier in the open ocean, and even if you have found it, difficult to target because it will be be moving at 30 knots in a zigzag pattern?

Aunche• 5 years ago

From what I understand, we aren't particularly afraid of hypersonic missiles because nobody even has defenses against conventional ICBMs.

HPsquared3• 5 years ago

Perhaps hypersonic missiles could play a part in ICBM defense. You need something very fast and maneauverable.

dd444fgdfg• 5 years ago

IMHO, the risk of nuclear war is higher than we think. Can you imagine the number of expected casualties of all-out-war with China? We've played this game before. Japan/WW2. The US _will_ nuke China and justify it under number of lives saved.

dragonwriter2• 5 years ago

. Can you imagine the number of expected casualties of all-out-war with China? We've played this game before. Japan/WW2. The US _will_ nuke China

Japan didn't have a nuclear second-strike capability with the range to hit the US. (Or, literally, any part of that taken independently.)

The US leadership can't even make a remotely plausible argument, after emerging from their bunkers after the exchange is done, to have “saved lives” by nuking China.

tkojames• 5 years ago

China is not going to nuke a carrier group sorry but that is insane. The second that happened say goodbye to entire world. There is reason we have boomer subs. One Ohio class sub could legitimately end the world.

throwawaylinux10• 5 years ago

One Ohio class sub could legitimately end the world.

Not even close. It carries about 200 low yield warheads. Not even enough for 1 each for 1/3rd of the cities in China if you could spread them out that far. There have been over 500 atmospheric tests, many with vastly higher yield and fallout, the biggest tests had yields equivalent to all 200 warheads combined.

One could strike a huge blow to China's capability to carry on war by destroying many of its large ports.

x86_64Ubuntu2• 5 years ago

What does hypersonic mean? I thought all missiles were largely supersonic, except for maybe cruise missiles.

heydabop• 5 years ago

Reading the article or simply typing "hypersonic" into Google would've gotten you an immediate answer, but it means faster than Mach 5.

mchristen• 5 years ago

In aerodynamics, a hypersonic speed is one that greatly exceeds the speed of sound, often stated as starting at speeds of Mach 5 and above.

dsr_• 5 years ago

It's a speed regime. Under Mach 1 is subsonic. From Mach 0.9 through 1.2 or so is transsonic. 1.0 and greater is supersonic. Above Mach 5ish is hypersonic.

Mach 25 is approximately orbital velocity, but since Mach is actually related to air pressure, it's not a very meaningful comparison except to note that anything moving that fast isn't going to be in-atmosphere for very long.

HPsquared3• 5 years ago

In subsonic flight, the air behaves as if it's incompressible (like a liquid).

In transonic flight, some parts of the airflow are starting to become supersonic, and compressibility starts to become a factor. Something called "wave drag" is important in this regime, as the compression wave is moving along with the aircraft.

In supersonic flow, compressibility of the air becomes the main thing and the flow is defined by the positions of the various shock waves. Ramjet engines work in this regime (the aircraft is moving fast enough that the forward movement is enough to compress the incoming air to the engine, without compressor blades). In a conventional ramjet engine, the flow within the engine is subsonic (the compressed air, being more dense, moves more slowly within the engine), so combustion works the usual way.

In hypersonic flow, temperatures are getting very high (air is heated by compression). Scramjet engines become a thing (the "SC" is for supersonic combustion: air flowing through the combustion stage at supersonic speed).

colechristensen2• 5 years ago

The speed of sound in air (or mixtures of diatomic gasses) is a function of temperature only, independent of pressure and density. Or it depends on pressure and density in a way which cancels out and leaves only temperature as an independent variable for equivalent mixtures of gasses. (i.e. the speed of sound is the same at 20 atmospheres or 0.1 atmosphere as long as the temperature is the same) This becomes untrue when air is very very hot or very very cold, but generally those conditions aren't experienced on this planet outside of hot hypersonic flight.

Water vapor content, not being a diatomic gas does very slightly change the speed of sound but usually to a degree which can be ignored.

(people generally don't believe that the speed of sound in air depends only on temperature when you tell them)

credit_guy2• 5 years ago

A good starting point is this Congressional report on hypersonic weapons, updated one month ago:

https://sgp.fas.org/crs/weapons/R45811.pdf

x86_64Ubuntu2• 5 years ago

Thanks, I've started reading it and will continue later, the material seems to be perfect for a non-Aerospace professional.

nielsbot2• 5 years ago

OMG "The Pentagon’s FY2022 budget request for hypersonic research is $3.8 billion"

mzs2• 5 years ago

Though it means mach 5+ in terms of weapons systems it indicates a capability for a long highly maneuverable period at those speeds.

https://www.gao.gov/blog/faster-speed-sound-u.s.-efforts-dev...

lumost3• 5 years ago

It's worth noting that at these speeds a "long" period need only be ~1 hour to reach a target from launch. A flight from Hawaii to Taipei would be 1.3 hours at Mach 5, and 54 minutes at Mach 7.

These weapons represent an ability for both the US and China to conventionally intervene from their mainlands to any location within the Pacific.

colechristensen2• 5 years ago

There aren't exact thresholds, but hypersonic generally refers to speeds fast enough that fluid heating can no longer be approximated away and chemical reactions and ionization in the air start to dominate.

Aerodynamics is a practice of which physical phenomena you can ignore. At low speeds you can pretend the speed of sound is infinite / air is incompressible (these are equivalent), as you get faster you have to start paying attention to compression, then shock waves, heating, ionization, and the mechanics of individual particles.

volta83• 5 years ago

And to give some examples, while you could maybe ignore ionization for the aerodynamics of an F22 travelling at Mach 3, you probably could not ignore them for a school bus travelling at Mach 3.

rektide2• 5 years ago

One key consideration that I only got recently is the difference between a cruise & ballistic missile. A ballistic missile launches at great velocity, then more or less falls at it's target (over an extended distance) using a ballistic trajectory. A cruise missile is under power for a large part of it's journey, typically flying much lower, & able to navigate/direct itself.

A ballistic missile is often quite supersonic. But cruise missiles being hypersonic is definitely a big shift.

foobarian• 5 years ago

I was pretty surprised by how slow cruise missiles are when I read up on them recently - similar to big airliner speeds. I always had a mental image of missiles as these "fastest in the sky" things that you could only dodge but not outrun. It's possibly true for Sidewinders but even they top out around Mach 2.5, so the hypersonic developments are a huge step forward.

Still kinda surprised there aren't fast missiles that use rocket engines. It works for ICBMs? I don't see a reason they couldn't maneuver as well. Maybe the hypersonic regime makes things novel not just for propulsion but control too.

Gravityloss• 5 years ago

Yes, extreme ends of the spectrum.

All ballistic missiles are hypersonic. The V-2 was hypersonic. That's because range is directly dependent on speed and you wouldn't have basically any range if you had a mere supersonic speed.

anovikov• 5 years ago

For a powered flight, it refers to the state where combustion in the engine happens at supersonic speeds (for a "normal" supersonic planes like fighters, it's subsonic because speed of sound in a heated air is much higher).

For an unpowered flight, it is a rather meaningless term, but normally refers to maneuvering warheads on ballistic missiles

sandworm101• 5 years ago

That is the difference between ramjets and scramjets, not necessarily the definition of hypersonic. And some "hypersonic" missiles don't breath air but rather conventional rocket motors to muscle their way to higher speeds.

The oldest definition of hypersonic I have heard is those speeds where compression heating of the atmosphere ahead of the craft generates plasma. A space capsule on reentry hits such speeds, causing the classic radio blackout. So hypersonic aircraft are those that must deal with plasma-related issues that are irrelevant to slower supersonic aircraft.

TrainedMonkey• 5 years ago

The HAWC is exploring air-breathing hypersonic flight
propelling the cruiser at a speed greater than Mach 5

I wonder if they are running a scramjet engine: https://en.wikipedia.org/wiki/Scramjet

heywherelogingo• 5 years ago

"In order for the scramjet engine to ignite,..."

HPsquared3• 5 years ago

These engines (ramjets, including scramjets - the 'sc' means supersonic combustion, which is the hard part) rely on forward airspeed to compress the air as it enters the engine. You can't have a ramjet without some sort of booster stage (or non-ramjet mode of operation).

In this case, there's probably a conventional rocket engine to get it up to speed, which is then sustained by the (sc)ramjet engine.

MilStdJunkie2• 5 years ago

There's a sort of fuzzy line betwwwn high supersonic and hypersonic, but the secret sauce that definitely separates them - and the hardest part by far - is supersonic combustion in the scramjet. You basically have to figure out how to make something sit still long enough to impart a thrust impulse, while at the same time sitting in an airstream that's starting to act like a cutting laser. Very little tech data from working scramjet shots have been made public, but it's likely the most successful use some kind of incredible heat exchange system to take at least some of the energy out of the flow. Maybe pipe it into the fuel.

The Skylon / Sabre engine justa went "fuck it" and liquified the air at lower speeds, then transitioned to liquified oxidizer like a rocket when hypersonic time came around. If that sounds like some kind of miracle heat exchanger that's because it is. It's not been worked out.

Pulse Detonation is something I always wondered why we didn't see more of it, but apparently when you make a PDE big enough it hammers the plane apart like an infant with a frying pan. Who knew?

alexisread• 5 years ago

As far as I know, the Sabre heat exchanger doesn't liquefy the air as frost kills the tubing. It cools down to the boundary without going over. I believe they've demonstrated mach 3 conditions but not mach 5, and they're on track

https://www.pprune.org/military-aviation/print-619462-reacti...

twic2• 5 years ago

The SABRE engine won't liquefy incoming air, it just cools it down a lot (to -150 C!). But SABRE is an evolution of a 1980s design, the RB545, designed for the HOTOL spaceplane, which would indeed have liquefied incoming air. The RB545 was in turn derived from a 1950s concept, LACE:

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

dirtyid6• 5 years ago

Interesting to ponder the US need for hypersonic capabilities. PRC + Russia needs it to asymmetrically challenge the USN. Not many time-sensitive targets for the US to hit in PRC or Russia outside of mobile TELs to take out road mobile nuclear forces. For context, US dumping ~4B into hypersonics = ~3000 JASSMs which is probably a better investment for peer naval warfare. Politically, this program feels like air force trying to stay relevant for China pivot, grabbing a slice of the pie, and obviously good for MIC.

echelon3• 5 years ago

The PRC is developing a blue water navy and is heavily ramping up on carrier shipbuilding.

It makes sense that the US would want to build similar, land-based defensive strategies as a deterrent.

dirtyid6• 5 years ago

The Air Force has said it plans to pursue both the ARRW and the Hypersonic Attack Cruise Missile (HACM), as initial and future hypersonic attack capabilities, respectively.

These are offensive standoff weapons launched from air designed to hit time sensitive targets. The question is really what targets, like I said, spending the money on 3000 JASSMs is already enough to sink every major PLAN combatants with room to spare. Need to consider what these hypersonics can hit that traditional standoff weapons can't. Or just the politics behind aquisition between branches. I'm not saying this is bad/wasteful defense spending, but curious what it's exactly for.

aidenn0• 5 years ago

Would a hypersonic SAM improve CV survivability against non-hypersonic cruis missiles?

dirtyid6• 5 years ago

This is an entirely different program than hypersonic defense on naval platforms. As far as I know Pentagon is focusing on lasers and advanced interceptor designs, and hopes to have something "workable" by the mid 2025s.

hmm320• 5 years ago

Don't the Russians have missiles that fly >5x faster than this, at mach 27?

thunderbird120• 5 years ago

Air breathing hypersonic missiles and hypersonic glide vehicles really shouldn't be compared. They have different operational uses. Air breathing missiles are slower but can also be significantly smaller and can fly for sustained periods at lower altitudes. This missile is more comparable to the Russian Zircon missile.

SonicScrub3• 5 years ago

That vehicle is a sub-orbital vehicle with a re-entry trajectory similar to a ballistic missile . It reaches it's highest speeds only at altitudes where the atmosphere is more individual particles than a continuous gas (it's apogee of 62 miles is well above the Karmen line). The definition of Mach number only makes sense within a fluid. A vehicle that travels 20,716 miles per hour is NOT travelling Mach 27. You can say it's travelling roughly 27 times the speed of sound at sea-level like conditions to get a sense of the scale of the speed, but it is not travelling Mach 27. Once it slams into the atmosphere on re-entry, you can say it is travelling at Mach 27, but by then it's not undergoing sustained flight. This specific vehicle is merely gliding.

This distinction is important, because all of the difficulties associated with flying at hypersonic speeds are due to the problems associated with flying through the fluid. It's comparatively easy to accelerate to the high speeds of sub-orbital vehicles once outside a meaningful atmosphere.

Militarily this is an important distinction as well. An intercontinental ballistic missile needs to go significantly above the earth's atmosphere. During this phase, it's easily detectable, since the horizon is much further away. A vehicle flying much lower well within the earth's atmosphere at very high speeds gives much less early warning.

This specific vehicle strikes a sort of middle ground between these concepts. It's half sub-orbital ballistic missile (it's still required to go above a meaningful atmosphere), half hypersonic cruise missile. Although very critically it is not undergoing sustained flight at hypersonic speeds

sbierwagen• 5 years ago

highest speeds only at altitudes where the atmosphere is more individual particles than a continuous gas (it's apogee of 62 miles [...] )

Isn't velocity lowest at apogee?

fnord772• 5 years ago

would a MARV-tipped ICBM be able to reach a target faster than flying straight at it at Mach 5?

I was looking for MARV reentry velocities, couldn't find any numbers. A regular ballistic missile hits mach 20+ on reentry but I don't know if it maintains that speed all the way to the target.

hindsightbias• 5 years ago

Marvs are just Mirvs that maneuver. They will go the same speed until they maneuver.

SonicScrub3• 5 years ago

From my understanding, the primary benefit of the Hypersonic Missile over the ICBM is not the speed of payload delivery, but the amount of warning given to the target. An ICBM needs to ascend 100s of kms, thus enabling it to be detected by very far away radar systems. Those same radar systems that would be over the horizon at the lower altitudes within the atmosphere. Launching an ICBM almost immediately announces to the world "I am launching a nuclear warhead", thus enabling countermeasures to be readied, and a retaliatory strike to be launched. The time between this warning and the strike is indeed small (measured in 10s of minutes), but that's much more time than a hypersonic missile gives.

nautilius4• 5 years ago

And the maneuverability - if you just adjust the course slightly ten seconds before impact, at these speeds, that’s a big difference. Ballistic mostly just falls down, i.e. you know what it will hit when you observe the launch (somewhat simplified).

kubanczyk3• 5 years ago

A regular ballistic missile hits mach 20+ on reentry but I don't know if it maintains that speed all the way to the target.

The word "ballistic" means it doesn't maintain the speed. Etymologically and practically it's about throwing a stone, i.e. finding out what happens when you give it an initial velocity with approximately zero delta-V budget for the main part of the flight.

But everything gets complicated with time, so there are now depressed trajectories (i.e. not-entirely-ballistic flight paths) for the ballistic missiles. But these still do not carry dramatic delta-V.

everyone• 5 years ago

I've read in a few places that the US is way behind China and others in hypersonic missiles. Would like to hear what HN has to say on that.

baybal22• 5 years ago

May be, but I don't understand the obsession regarding hypersonic missiles.

There are dozens of other surprise attack weapons to knockout a superpower level enemy to select from. Hypersonic weapons are just few of them.

It's more of a psychological weapon as ICBMs are. As in most cases, a new wunderwaffe will lose out to oldschool war tricks.

sudosysgen15• 5 years ago

Really not. Hypersonic missiles are a game changer because, without any risk of escalation, they are un-interceptable and can hit very important and high value assets very fast without requiring survivable targeting platforms.

sudosysgen15• 5 years ago

Russia is finalizing field tests of hypersonics that are due to be deployed on ships in less than a year, and has actually fired them from ships at targets.

China is more secretive but there is evidence there were at this stage 5+ years ago.

HappySweeney• 5 years ago

Why be secretive about this stuff? Isn't its whole raison d'etre to be a deterrent in the face of American anti-missile systems? Or is this something more like a Corbomite Maneuver?

Hypersonic HAWC missile flies, but details are kept hidden

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