[HN Gopher] U.S. Air Force says it conducted successful hyperson...
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U.S. Air Force says it conducted successful hypersonic weapon test
Author : prostoalex
Score : 65 points
Date : 2022-05-17 16:26 UTC (6 hours ago)
(HTM) web link (www.reuters.com)
(TXT) w3m dump (www.reuters.com)
| cersa8 wrote:
| 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...
| MR4D wrote:
| 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...
| godelski wrote:
| Just note that hypersonic weapons are also used defensively.
| There's research into using them to take out ICBMs during the
| boost phase. This is the only part of the missile sequence
| that has a high chance of neutralizing the missile threat but
| also the most difficult phase to counteract.
| ortusdux wrote:
| See also: Supercavitating torpedos, which reportedly can
| travel at 300-350 mph.
| JoeAltmaier wrote:
| And destroyed the first submarine that tested them!
| Russian, the typical failure of a new torpedo is guidance,
| which often results in the device describing a circular
| route instead of a straight one. Ending up back where it
| started. So they fired, and before you could say Jack
| Robinson it hit them, having traveled in a circle of a mile
| or so.
|
| Or so I recall from reports after the fact.
| dirtyid wrote:
| 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.
| Victerius wrote:
| > build up enough JASSMs to last until WW5
|
| Love the imagery.
| rad88 wrote:
| Honest question, how would you describe MAD as being
| practical? Bearing in mind that the treaties to maintain it
| were abandoned, and both sides invest (and act) heavily in
| rocking the boat?
| idiotsecant wrote:
| I think it's hard to argue that MAD isn't in effect right
| this second. If there was no threat of massive retaliation
| and possible resulting extinction is there any doubt Russia
| would have used nuclear weapons in it's Ukraine invasion?
| rad88 wrote:
| Why would they? There are 8 million Russians living in
| the country, and close social ties besides. Putin
| consistently lies and says 80% of the population is
| Russian and that Ukraine _is_ Russia. Plus the fact that
| Russian people are generally not psychopathic murderers,
| the invasion could only be acknowledged as a limited
| operation, they depend on the world and European
| economies, the military destroyed other countries
| /regions far away from NATO and then had no need for the
| atom bomb either... yes I think there's room for doubt.
| idiotsecant wrote:
| >Why would they?
|
| Because they would win with the resources they have
| available. It's not that complicated.
| rad88 wrote:
| I see. You don't realize that they are already going to
| "win".
| zozin wrote:
| 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.
| secondcoming wrote:
| 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.
| cracrecry wrote:
| This is not Marketing. This is a real thing.
|
| It is a real thing that they can put a several nukes in one
| of those and kill the entire population of New York, or
| London, or Paris in five minutes.
|
| Also it is real that Putin has used exactly that card, that
| threat as a negotiation tactic, in order to get away with
| invading a foreign country, in order to compensate for the
| joke of a country they are.
|
| Putin has specifically said that: that he developed those
| weapons, that they can be nuclear and no country can
| neutralize them.
|
| History teaches us that accommodated Societies usually fall
| under much primitive rules like the Mongols with Genghis
| Khan, or the Huns, The Romans (against the Greeks), the
| Germanic tribes(against the Romans), the Arabs(against the
| Persian and Byzantine empires), the British against the
| Spanish Empire, the Russians against the Germans and so on.
|
| The US, or UK, France, Poland or Germany just can't ignore
| it, whenever they like it or not. There is someone out there
| telling Ukraine is their property or else.
|
| They need to develop a neutralization of those weapons.
|
| A country just can't ignore an Arms race if the adversary
| follows it, they have to follow as well.
| nimbius wrote:
| 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 until it
| appeared on radar over Canada. When the RQ710 was deployed in
| Iran with the same arrogant impunity, it was intercepted,
| landed, and dissected. heck, we spent about two decades
| insisting we could depose a cuban leader and just as long
| insisting we would "win" against the taliban.
|
| and when the united states assumed china incapable of a
| cryptographic advantage, the nation summarily identified and
| executed more than a dozen spies thanks in part to dismissive
| hubris.
|
| https://www.reuters.com/article/us-usa-china-espionage-
| idUSK...
|
| the absolute worst thing you can do is dismiss a capable
| enemy.
| greedo wrote:
| 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.
| tablespoon wrote:
| > The US also overestimates the threats from its
| potential adversaries quite frequently.
|
| Yeah, for instance, IIRC, the F-15 (at least partially)
| resulted from a severe over-estimation of the
| capabilities of the Mig-25.
| robonerd wrote:
| 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.
| ramesh31 wrote:
| >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.
| greedo wrote:
| 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.
| robonerd wrote:
| Presumably addressing this threat is what America's 50+
| SSNs are for.
| greedo wrote:
| Presumably, but the ocean is a big place. Now todays
| threats are far different than at the peak of the Cold
| War. The Russian SSBN fleet is a shell of itself, and the
| PLAN is still just dabbling in sub-based deterrents. The
| diminished threat is matched by the absolute disrepair of
| USN anti-sub warfare skills. These have atrophied beyond
| description in the last 30 years.
| Aunche wrote:
| 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.
| towaway15463 wrote:
| 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.
| tmccrary55 wrote:
| If only someone had directed energy weapons...
| rad88 wrote:
| A ballistic missile could be within a few hundred miles
| of any point near the coast and be there in less than 5
| minutes. You're saying this is "trivial" to intercept,
| what does that mean?
| hungryforcodes wrote:
| Existing. Soon to be found.
| robonerd wrote:
| 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.
| ramesh31 wrote:
| >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.
| hdjjhhvvhga wrote:
| I think it is definitely a problem: not because we do not
| actually have the tech required (I believe we do, to some
| extent), but because Putin has so broken intelligence
| process he might come to the conclusion we don't, and
| makes some stupid moves because of that (although I'd
| have found this idea laughable ta best before 24
| February). Therefore I expect a couple of carefully
| worded Reuters articles related to successful
| intercepting mach 5 missiles at first.
| thereddaikon wrote:
| >Except the associated plasma shielding makes it
| invisible to radar.
|
| You mean makes it very visible to radar but blocks any rf
| emissions to and from the vehicle itself right? This is
| no different than reentry effects we see on spacecraft.
| They are easily tracked by radar but have a radio
| blackout period until they slow down enough.
|
| >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.
|
| The Russian missile is a paper invention for propaganda.
| It effectively does not exist. And if it does then they
| only built one. It is not an operational weapon and never
| will be. Russia is a poor country that is run by thieves
| who siphon money from their military to buy mansions and
| yachts. Just like T-14 and Su-57, Zircon is a propaganda
| wunderwaffe that will never be in combat.
|
| China is bigger problem. But at the moment they have just
| fielded boost-glide vehicles. Not scramjets.
| throwaway0a5e wrote:
| >Except the associated plasma shielding makes it
| invisible to radar.
|
| Anything moving mach 8 is gonna light up like a Christmas
| tree in other parts of the EM spectrum.
| robonerd wrote:
| > _Except the associated plasma shielding makes it
| invisible to radar._
|
| All hypersonic ballistic missile reentry vehicles have
| this plasma stealth. That doesn't stop Aegis BDM from
| tracking and intercepting them. Have you ever seen a
| reentry vehicle coming in? They're as bright as
| meteorites, very easy to see.
|
| > _And the Russian ones are capable of sea skimming and
| maneuvering at mach 8 in the terminal phase._
|
| These are the hypersonic cruise missiles; very different
| from hypersonic boost-glide missiles. This is what I mean
| about the media talking about "hypersonic" generically
| without specifying the technology they're actually
| talking about; it leads to people believing that
| 'hypersonic' is itself the technology.
| [deleted]
| hdjjhhvvhga wrote:
| 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.
| greedo wrote:
| 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.
| rad88 wrote:
| SSSHHHHHHHH we need more atom bombs! Raytheon has what we
| need!
| thereddaikon wrote:
| 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 harder to hit.
|
| The weapon the air force tested today is similar to that
| but meant to be launched from bombers instead of ground
| launched.
|
| The actual scary ones are hypersonic cruise missiles.
| Nobody has fielded one operationally yet. But the US is by
| far the furthest ahead in this technology. In march they
| had a successful test of HAWC the Hypersonic Air-breathing
| Weapon Concept. Scramjet powered cruise missiles like HAWC
| are more dangerous than conventional ballistic missile or
| boost-glide missiles because they actually fly. And
| therefore can do the things normal cruise missiles like
| Tomahawk can do. They can take circuitous routes. They can
| change their altitude. They can fly somewhat evasively.
| They can fly to an area and pick targets of opportunity.
| And other things.
|
| Why does it matter? We've gotten much better at shooting
| down conventional cruise missiles. A few years back an
| Arleigh Burke destroyer had a number of Chinese built
| subsonic anti ship missiles fired at it by Houthi Rebels.
| It shot down every single one of them. These missiles are
| comparable to the Neptunes that recently sank Moskva in
| terms of performance. So modern warships aren't as
| vulnerable as Soviet era antiques. You need better weapons
| to kill them. hypersonic cruise missiles are much harder to
| intercept. Boost glides are of dubious utility in my
| opinion.
| sudosysgen wrote:
| 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.
| ramesh31 wrote:
| >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.
| hungryforcodes wrote:
| 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.
| steve76 wrote:
| bparsons wrote:
| The Pentagon does this every decade. They constantly need
| some sort of existential threat to respond to in order to
| justify budget increases.
| booi wrote:
| 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.
| moron4hire wrote:
| They have to know what to hit and make sure the target
| they are tracking is actually a real target.
| robonerd wrote:
| > _Current Aegis and CIWS defensive tech will not hit
| something traveling that fast._
|
| Aegis BDM is designed to hit hypersonic reentry vehicles.
| CIWS is irrelevant, why even bring it up?
| ramesh31 wrote:
| >Aegis BDM is designed to hit hypersonic reentry vehicles
|
| _Ballistic_ hypersonic reentry vehicles. The entire
| point is that these new weapons are maneuverable in the
| atmosphere at mach 8+ all the way to the terminal phase.
| robonerd wrote:
| They don't maneuver for shit in the terminal phase.
| Boost-glide weapons avoid mid-course interception by
| staying _relatively_ low in the upper atmosphere rather
| than following a high ballistic trajectory well into
| space. Once they 're in the terminal phase their
| maneuvering capability is comparable to older maneuvering
| reentry vehicles (which are nothing new; the novel part
| is skipping the ballistic mid-course phase.)
| ARandomerDude wrote:
| Consider the possibility that technology changes with
| each decade and the previous system is...you know...now
| obsolete.
|
| I assume you have a smart phone and not an Amiga. By
| analogy, if your enemy has "iPhone" level weapons, would
| you want to face them with an "Amiga" level weapon? I
| doubt it.
| rad88 wrote:
| I don't know whether MIRVs, each carrying a dozen or so
| atom bombs, compare to HGVs like the Amiga does to the
| iPhone. I'd like to say absolutely not but I can't.
| Either way calling ballistic missiles "obsolete" is
| incomprehensible to the dead.
| RobRivera wrote:
| the perfect cover for funneling money into Metal Gear
| ritwikgupta wrote:
| Hypersonics are already being used in warfare today [1][2][3].
| They are already practical weapons and gaining parity in
| offensive and defensive capabilities is critical.
|
| [1] https://www.cnn.com/2022/03/22/europe/biden-russia-
| hypersoni...
|
| [2] https://www.defenseone.com/threats/2022/05/russia-has-
| fired-...
|
| [3] https://www.euronews.com/2022/05/10/russia-fires-
| hypersonic-...
| rad88 wrote:
| > Russia is thought to have an HGV in its arsenal.
|
| > ..
|
| > But the Kinzhal, as a variant of the Iskander SRBM, is not
| an HGV
| staunch wrote:
| 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?
| HWR_14 wrote:
| I imagine the use case is more conventional weapons, for
| example taking out a navy flagship.
| Buttons840 wrote:
| 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)
| coding123 wrote:
| Nukes simply existing may have saved more lives at this
| point. That could, of course, change in seconds at any time.
| manachar wrote:
| 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.
| aidenn0 wrote:
| Ask Putin about how useless having nukes is for preventing
| NATO involvement in the Ukraine...
| kcb wrote:
| > US missile defense system, which the US doesn't really even
| have
|
| Uh..Missile defense is a massive part of US Navy doctrine and
| is pretty much the primary purpose of every Destroyer, Cruiser,
| and soon Frigate in the Navy at this point.
|
| Without a doubt, the Aegis system and THAAD are the direct
| reason for these developments from China and Russia.
| gsibble wrote:
| This. We have hundreds of Aegis boats sitting off our coasts
| waiting for it to rain MIRVs.
| robonerd wrote:
| > _We have hundreds of Aegis boats_
|
| 113, if you count Japan's, Korea's, and the rest of NATO
| (with 137 more planned.) These are spread around the world,
| and only some of them are Aegis BMD. And not all of those
| will be ready when they're needed. A few dozen Aegis BMD
| ships off the coast of the US seems plausible.
|
| Besides Aegis, there is THAAD (which only protects a
| handful of rather small areas) and GMD (which only has a
| few dozen interceptors.) If China/Russia threw hundreds of
| missiles at the continental US all at once, it's a good bet
| that at least some would get through and wreck havoc.
| staunch wrote:
| Sure, but that doctrine is old. And has it not been partially
| obsoleted by China's advances in missile technology?
|
| My understanding was that our fleets have sufficient defense
| for a limited attack but that a full scale missile attack by
| China would quickly overwhelm them.
| kcb wrote:
| Aegis is continually evolving with new sensors, processing,
| and missiles and far from obsolete. It's no coincidence
| that China is building similar capabilities into its own
| Destroyers.
|
| I definitely would't call the scale of missile defense in
| the fleet limited. Each carrier group would contain and be
| screened by Destroyers and Cruisers with several hundred
| interceptors ready to go between them.
| greedo wrote:
| Waiting for the F-35 haters to hijack this thread...
| ortusdux wrote:
| It was an AGM-183 ARRW. The test on the 14th hit Mach 5, but they
| claim a theoretical top speed of Mach 20.
|
| https://en.wikipedia.org/wiki/AGM-183_ARRW
| rootusrootus wrote:
| Reading through the timeline on that page, it sounds like
| Congress has decided to kill the project. I wonder if this
| successful test will turn that around.
| riku_iki wrote:
| It says they transferred half of funds from procurement to
| R&D, probably because previous tests failures.
| KennyBlanken wrote:
| Biden's bumping up the military budget by tens of billions of
| dollars, that's what's turning this around.
|
| We finally got ourselves out of the Middle East, but we gotta
| keep the military-industrial complex fed, I guess. We already
| spend more total and per capita than the next top ten
| countries combined.
|
| It's so sad. We could do so much domestically, or just worked
| on influencing foreign policy by helping other countries,
| instead of military force projection.
| ortusdux wrote:
| From Lockheed's press release:
|
| _Additional booster and all-up-round test flights will
| continue throughout 2022, before reaching Early Operational
| Capability (EOC) in 2023._
|
| So it sounds like they found the cash somewhere.
|
| https://news.lockheedmartin.com/2022-05-17-us-air-force-
| and-...
| [deleted]
| FredPret wrote:
| Mach 20 is so fast. It's around the Earth at the equator
| (ground level) in two hours.
| HPsquared wrote:
| Orbital speeds within the atmosphere, basically.
|
| Edit: I suppose that means the vehicle wouldn't need any
| aerodynamic lift when going at full speed; indeed, to
| maintain altitude it'd need _negative_ lift.
| SkyMarshal wrote:
| _Barely_ within the atmosphere, I assume. Mach 20 at
| commercial jet altitudes would probably melt the aircraft.
| Victerius wrote:
| Just build your aircraft out of titanium.
| *cough*SR-71*cough*
| SkyMarshal wrote:
| I said Mach 20, not Mach 3.
| FredPret wrote:
| Wonder if this would be much of an issue for a missile.
| It can melt away on the outside to a degree, as long as
| the payload gets there intact. And it can get anywhere on
| the planet in an hour, so perhaps a sacrificial shield
| would work.
| elEpHantiaSis wrote:
| oneoff786 wrote:
| 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?
| hammock wrote:
| Look up "rods from God."
|
| https://en.wikipedia.org/wiki/Kinetic_bombardment
|
| https://www.businessinsider.com/air-force-rods-from-god-
| kine....
| mywittyname wrote:
| It always baffled me that these weren't named after Zeus.
| djmips wrote:
| I think there might be a grammar problem in your statement.
| What did you mean?
| Buttons840 wrote:
| He means how fast does a missile need to go so that the
| kinetic energy is greater than the chemical/explosive energy.
| jstanley wrote:
| It's relatively common to use "anymore" to mean "nowadays".
|
| I think it must have come from hearing things like "They
| don't do that any more" and not recognising "any" and "more"
| as separate words, but rather as a concept that just means
| "now", such that "They do that anymore" is equally valid.
| djmips wrote:
| Wow really? I missed out on that one. Thanks for the
| update.
| oneoff786 wrote:
| https://ygdp.yale.edu/phenomena/positive-anymore
|
| I picked it up from Pennsylvania unintentionally. Not a huge
| fan of it tbh.
| zmgsabst wrote:
| 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)
| theptip wrote:
| 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?
| zmgsabst wrote:
| Per OP:
|
| > The U.S. Air Force said on Monday it had conducted a
| successful test of a hypersonic weapon, which flew at five
| times the speed of sound.
|
| But to your question:
|
| > around Mach 10-20 is where the tradeoff could become non-
| obvious, depending on how much you value weighing less?
|
| The same logic holds at mach 5-8 (ie current hypersonics),
| which is why they're being developed:
|
| You want a weapon that can surprise, evade, or penetrate
| better -- even if that's less destructive overall.
| adrian_b wrote:
| When close to the ground, something flying at Mach 10-20
| would either be deccelerated very quickly to much lower
| speeds, if flying passively, or require a very large mass
| of fuel to maintain the speed.
|
| Moreover, it would be hard to avoid being partially
| vaporized before reaching the target. So hitting something
| at Mach 10-20 seems much more difficult than filling the
| missile with explosives and detonating it.
|
| Weapons based on kinetic energy alone seem practical only
| against satellites or against targets that fly in the upper
| atmosphere.
| aidenn0 wrote:
| About mach 8, but then you need to actually hit your target.
|
| For ground based targets that's probably fine (in fact for
| slow-moving, armored targets kinetic-energy penetrators are
| already a thing). For anti-aircraft fire the goal is to get
| "close enough" that the explosives will damage it.
| michael1999 wrote:
| 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
| robonerd wrote:
| > _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.
| michael1999 wrote:
| 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.
| sandworm101 wrote:
| >> "Following separation from the aircraft, the ARRW's booster
| ignited and burned for expected duration, achieving hypersonic
| speeds five times greater than the speed of sound," it said.
|
| Big deal. The booster is just a rocket. And Mach numbers are
| meaningless without altitude reference. Anything that travels to
| the outer atmosphere/space will hit extreme Mach numbers on the
| way up/down. So without any further data the above statement
| means little more than "we fired a big rocket". Did the
| sustainment motor, the air-breathing thing that differentiates a
| true hypersonic from every other rocket, did that motor function
| in cruise mode? Or is this essentially just a boost-glide
| ballistic missile?
| nilstycho wrote:
| The ARRW boost-glide vehicle is unpowered, but maneuverable.
| This test used a dummy boost-glide vehicle, though. They
| haven't disclosed if releasing the dummy vehicle was part of
| this test, and if so whether it succeeded. This test was just
| testing the boost phase.
|
| edit: From the Lockheed Martin press release
| (https://news.lockheedmartin.com/2022-05-17-us-air-force-
| and-...):
|
| > The successful flight demonstrates the weapon's ability to
| reach and withstand operational hypersonic speeds, collect
| crucial data for use in further flight tests, and validate safe
| separation from the aircraft to deliver the glide body and
| warhead to designated targets from significant standoff
| distances. ... Additional booster and all-up-round test flights
| will continue throughout 2022, before reaching Early
| Operational Capability (EOC) in 2023.
| nathanyz wrote:
| Probably just us flexing that we have them too. Likely have had
| them, but kept it quiet as no need to declare our capabilities.
| Since others are crowing about it, just letting them know we also
| have same.
| jaywalk wrote:
| Absolutely. I also don't believe that they "only" go 5x the
| speed of sound. That's most likely just the speed they're
| willing to disclose, and the actual speed is classified.
| Zandikar wrote:
| I mean, our X-15 was a manned hypersonic aircraft (by a good
| margin of the minimum 5x speed) in the 1960's, and ICBM's
| have been guided unmanned long range hypersonic munitions
| since a similar era, just to name a few. We have plenty of
| experience with hypersonics, and we almost certainly have
| continued research and experimentation into the field.
|
| The real technological linchpin isn't so much the speed, but
| would be things like guidance, precision and manuevering at
| those speeds, or perhaps other things like stealth, heat
| management materials (lot of friction from the air when
| you're ripping through it at those speeds), transatmospheric
| flight, advancements in hybrid (sc)ramjet engines, etc.
|
| Going hypersonic in and of itself is nothing new. We've been
| doing that since the 60's. Shit we made a manhole cover go
| hypersonic before the Russian's ever launched sputnik. It's
| what something can do after its moving at hypersonic speed
| that's of real consequence.
| [deleted]
| nipponese wrote:
| Yes, but only because our Congress is trying to make political
| theater of the topic.
|
| https://www.youtube.com/watch?v=qz_2r6rWgY8
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