DARPA's hypersonic scramjet achieves successful flight | Hacker News Reader

DARPA's hypersonic scramjet achieves successful flight

darpa.mil

161 pointsgeox198 comments

US's answer to Russia's Zircon missile?

https://www.military.com/equipment/weapons/why-russias-hyper...

> U.S. Aegis missile interceptor systems require 8-10 seconds of reaction time to intercept incoming attacks. In those 8-10 seconds, the Russian Zircon missiles will already have traveled 20 kilometers, and the interceptor missiles do not fly fast enough to catch up.

Pretty much and a counter against Chinese Hypersonic glide vehicles.

I'm not convinced you want air breathing missiles for interception, you want solid rockets or something of that sort. There are Standard Missiles (SM-3) faster than Zircon, although they are for BMD defense.

Faster ESSM/SM-2/SM-6 could be developed, and reaction time could be lowered.

This is instead the equivalent to the Zircon.

The Sprint[1] missile accelerated at 100g. That's 0-mach 10 in 5s flat. It flew so fast in the lower atmosphere that it glowed white hot.

So, just saying there were some pretty fast missiles decades ago. There was also the HIBEX missile, with 400g acceleration.

[1] https://en.wikipedia.org/wiki/Sprint_(missile)

Not quite sure why interceptor missiles would have to "fly fast enough to catch up" unless you're shooting at a missile departing from you (that is to say, unless you actually have to catch up with something).

You don’t always have missile interceptors on the target land. Aegis is a mobile platform that can be deployed anywhere, and being overflown is a real possibility. For example, your missile defense platform might be off the coast several km, and the target to intercept flies over it aiming for the land behind it. In this scenario, any interceptor launched from that platform would have to “catch up.”

No, it would just have to reach the target interception area in time. That's not quite the same as "catching up", although of course the possible radius within which this area must be located shrinks as a function of speed ratios.

And if by "flies over it", you meant the defense system as "it", that's still effectively point defense. Although this particular situation is unlikely for obvious reasons; the chance that your defense system would be exactly below the flight path of a missile while not being its target is small.

No. Russian Zircon is to deal with the next after nuclear strategic threat to Russia - US aircraft carrier groups. US pursue hypersonic weapons for different purpose - fast global much less than nuclear strike capability, ie. being able to strike any given target anywhere in like under half an hour. And thus not really much of hypersonic development in US - the cheap ballistic would do it better, especially with SpaceX driving down the cost of it. DOD is already excited that almost immediate delivery of 100ton, ie. instead of several C-130, payload by Starship anywhere in the world looks to be under $50M.

> US pursue hypersonic weapons for different purpose - fast global much less than nuclear strike capability

Ballistic missiles fly much, much faster than hypersonics. Speed is not their advantage.

Ballistic missiles give of bright, very hot exhaust plumes on leaving their silos. Any major world power with a down looking infrared satellite (or watching for "WTF was that launch in my wheat field" tweets from farmers"), will know when it launches, and have a relative idea of where it's headed and when it will land.

A hyper-sonic cruise missile is much more stealthy, giving it the element of surprise.

> The HAWC vehicle operates best in oxygen-rich atmosphere, where speed and maneuverability make it difficult to detect in a timely way.

I'm reasonably sure that the infrared trace of a hypersonic vehicle doesn't make it difficult to detect. Likewise existing approaches to radar stealth are hard to reconcile with hypersonic speeds, which doesn't help avoid radar detection either.

Plasma stealth is an existing approach to radar stealth that is made easier by hypersonic speeds.

Infrared targeting of multiple hypersonic missiles is easier said than done. The missile you're hitting them with is going to be heating up the air around the camera probably at the same temps as the missile it's intercepting, and a base station wouldn't have enough resolution to guide a missile accurately from 100+km away while being alert for other missiles.

> The missile you're hitting them with is going to be heating up the air around the camera probably at the same temps as the missile it's intercepting

That would only apply if it were to hit it at comparable speeds. That's not necessary in many cases, especially in point defense when the target is heading towards you. Furthermore the limited time of flight of the interceptor might also allow for active cooling of the IR window in that brief period.

Also, even detection from a fixed ground base (or from space - see SpaceX's newest missile detection project) is still detection in the first place, which is what I was commenting on. Wasn't even going to veer into interceptor guidance, but I'm sure there's multiple ways to do it.

Interception against an actively manoeuvring target is a question of kinetic energy. If the intecepting missile is smaller all the hypersonic missile has to do is zig-zagging randomly and you're toast.

If you're going to wait for the hypersonic missile to be close enough that this isn't a problem, you have the issue that your missile won't be able to manoeuvre right and might still be building up velocity. Plus there won't only be one!

> the interceptor might also allow for active cooling of the IR window in that brief period.

The issue isn't the IR window, it's the air directly in front of the interceptor missile, which has to target from the frontal aspect.

>Also, even detection from a fixed ground base (or from space - see SpaceX's newest missile detection project) is still detection in the first place, which is what I was commenting on. Wasn't even going to veer into interceptor guidance, but I'm sure there's multiple ways to do it.

Detection is not enough. We can already detect missiles from satellites even. The issue is calculating their velocity accurately and locating them at +- 10m from 100km+ away is not feasible without really large apertures and pretty long focal lengths. You wouldn't be able to accurately track more missiles than you have optics and the optics would be mind-boggingly expensive. Besides that, the target acquisition radar to maintain a feasible or even physically possible relative aperture for target acquisition would be unable to resolve any detail about the missile, so it would have no way of telling the difference between a missile and a flare of the same brightness and color.

> Interception against an actively manoeuvring target is a question of kinetic energy. If the intecepting missile is smaller all the hypersonic missile has to do is zig-zagging randomly and you're toast.

What you're describing is not a matter of kinetic energy (clearly if it were about kinetic energy, this would be defeated by making the interceptor weigh 30 tonnes) but a matter of transverse acceleration. On that matter, as far as I understand it, current AAMs/SAMs are somewhere in the 50g region. I strongly suspect that hypersonic vehicles due to their lower L/D are nowhere near that -- hell, many of them seem to have a hard enough time flying straight, if US military's experience is of any relevance here.

Also, due to low L/D ratio in the high Mach region, if your missile is zig-zagging randomly, it won't stay fast for long. And if it's not zig-zagging randomly, then the question is how it gets the information how to zig-zag, since the nose of a hypersonic vehicle seems to be an extremely poor sensor platform -- which you admitted yourself. It's virtually certain that it won't be able to see the interceptor.

> The issue isn't the IR window, it's the air directly in front of the interceptor missile, which has to target from the frontal aspect.

It seems unlikely that the interceptor will have to fly at a comparable speed in a frontal aspect interception situation (considering that it doesn't need to catch up).

But as for terminal interception, I suspect that here the inverse-fourth-power-of-distance operation of an active radar homing solution might help you if all else fails -- at a small enough distance this will work even better than the inverse square applicable to passive optical/IR detection.

> would be unable to resolve any detail about the missile, so it would have no way of telling the difference between a missile and a flare of the same brightness and color.

It would seem that the easiest way to distinguish a flare would be to look if it's in a controlled flight? Unlike a flare, the hypersonic vehicle will continue flying, and the difference is readily apparent. Besides, you can't have that many flares on it, so you can't keep firing them continuously -- again, the only thing that's available to you if you can't see the incoming interceptor.

>What you're describing is not a matter of kinetic energy (clearly if it were about kinetic energy, this would be defeated by making the interceptor weigh 30 tonnes) but a matter of transverse acceleration. On that matter, as far as I understand it, current AAMs/SAMs are somewhere in the 50g region. I strongly suspect that hypersonic vehicles due to their lower L/D are nowhere near that -- hell, many of them seem to have a hard enough time flying straight, if US military's experience is of any relevance here.

Not so. AAMs/SAM can only pull anywhere close to 50g at gigantic cost in drag and can only do that once and briefly. It is a question of kinetic energy because the missile that can regenerate kinetic energy and that loses the least kinetic energy relative to it's mass is at a massive advantage.

>Also, due to low L/D ratio in the high Mach region, if your missile is zig-zagging randomly, it won't stay fast for long. And if it's not zig-zagging randomly, then the question is how it gets the information how to zig-zag, since the nose of a hypersonic vehicle seems to be an extremely poor sensor platform -- which you admitted yourself. It's virtually certain that it won't be able to see the interceptor.

Traditional aerodynamic designs suffer from poor L/D ratios, yes. Waverider designs probably have much fewer issues. Given the advent of HGVs, which are made to turn multiple times without any engine to back them up, we can be fairly confident that this is not the case.

As far as being a poor sensor, this is an oversimplification of a complex mechanism. Plasmas block radar up to a certain frequecy depending on their temperature. So you make it so that the radar is somewhere where the air is slightly colder and make its frequency higher. You don't even have to put the radar in the nose if the target you're trying to hit is sluggish and large enough.

It doesn't need to maneuver in response to the interceptor. The missile knows when it is in LOS to the target, and knows that the interceptor will be fired soon after. So it already knows when the missile will be fired and thus when the missile would hit. The window for interception is pretty short. It would have to do evasive maneuvers at maybe 4G for maybe 30 seconds, all the while gaining back Ke from reducing in altitude in combination with engines.

>It would seem that the easiest way to distinguish a flare would be to look if it's in a controlled flight? Unlike a flare, the hypersonic vehicle will continue flying, and the difference is readily apparent. Besides, you can't have that many flares on it, so you can't keep firing them continuously -- again, the only thing that's available to you if you can't see the incoming interceptor.

This is a REALLY hard problem, and it's the reason why imaging infrared guidance was invented. It takes a lot of time to be certain that a flare in a ballistic trajectory at high speed is different from a missile coming towards you! Those are precious seconds you can't afford. Remember that you have no way of estimating distance.

> Not so. AAMs/SAM can only pull anywhere close to 50g at gigantic cost in drag and can only do that once and briefly. It is a question of kinetic energy because the missile that can regenerate kinetic energy and that loses the least kinetic energy relative to it's mass is at a massive advantage.

Except since the interceptor has only one chance at interception, the situations of the interceptor and the missile are not symmetrical. "Doing that once and briefly" seems quite acceptable for the interceptor. The missile pretty much must regenerate kinetic energy, or its subsequent suboptimal flight regime might make it even more vulnerable to the second interceptor incoming, or the third one after that.

> The window for interception is pretty short.

With early detection (orbital, for example), the window seems to be as long as the range of the longest-range applicable interceptor missile.

> It would have to do evasive maneuvers at maybe 4G for maybe 30 seconds

That definitely seems to be a "too little, too late" kind of situation. Especially in a point defense scenario where maneuvering away from your line to target means not hitting the target in the first place (which is as good as a successful hit of the interceptor), and where being close to the target really favors the short-range defense systems.

> Remember that you have no way of estimating distance.

You may very well have that way in the end if SpaceX's/L3Harris's system gets implemented.

>> It would seem that the easiest way to distinguish a flare would be to look if it's in a controlled flight?

"This isn't one of your church picnic flare gun firings". Smarter people than Homer have been working on flare technology for 40+ years.

(2003) https://www.nationaldefensemagazine.org/articles/2003/11/30/...

>> Also, due to low L/D ratio in the high Mach region, if your missile is zig-zagging randomly, it won't stay fast for long.

These are not airplanes with wings. These are missiles very high in the atmosphere flying complex flight paths more accurately describes as trajectories. The air is thin, the drag low, the energies extraordinarily high. A successful zig-zag maneuver could be as small as one degree left or right, up or down. And sacrificing speed to escape an interceptor is a valid tradeoff considering that, not being an airplane, the missile intends to slam into the ground/target in a minute or two no matter what its speed.

  > Plasma stealth is an existing approach to radar
  > stealth that is made easier by hypersonic speeds.

Does a vehicle traveling at such speeds that it compresses the air into a plasma have much aerodynamic control? I am aware that the space shuttle orbiters would roll during the plasma stage to control their rate of decent (less lift vector in the "up" direction) but could a missile maneuver to a target? Assuming that the sensors-through-plasma issue were resolved (which is another issue that I do not believe can be easily resolved).

Isn't the point of these weapons that even if you can detect them they are too fast to intercept?

> even if you can detect them they are too fast to intercept?

No. They still travel far slower than ballistic missiles. Their advantages are in being able to fly low and (theoretically) manoeuvre to avoid interceptors.

They’re an evolution of cruise missiles, not strategic ballistic missiles.

But maneuvering at high velocities won't be that easy. As far as I understand it, your lift/drag ratio decreases appreciably with increasing Mach numbers. So either you'd have to limit your maneuvering, or you'd have to have a propulsion unit with ridiculous amounts of thrust - at a situation when any amount of useful thrust is hard to obtain, since we still don't know really well how to do propulsion in this regime.

As a former aerospace engineer, I’m sceptical of the strategic value of hypersonics. Tactical? Sure. They’d have a better chance of taking out SAMs, light radar, et cetera. But the talk about these being carrier killers is, based on everything we’ve seen, off the mark. (Spending the cost of one hypersonic on a swarming attack would probably do more damage.)

The biggest difference between hypersonics and swarms of slow missiles is that the hypersonics can get there fast enough that you might not need high-quality targeting information. That's definitely a strategic advantage!

Also the 3M22 is estimated to only cost around 2 million dollars.

> hypersonics can get there fast enough that you might not need high-quality targeting information

The strategic systems hypersonics are hyped to hit have been hardened against ballistics. Hypersonics are slower than ballistics. (Their plasma envelope also makes them easier to track by satellite.)

This is a tactical evolution. Meaningful. Helpful. But not a strategic shift.

The big issue is that a ballistic missile may not be able to deviate as much from the expected position as it can search away from it.

I agree that they're not that different from ballistics but they still have considerable advantages.

> that you might not need high-quality targeting information

I don't see how this would work, unless of course you're talking about nuclear weapons. With a conventional warhead you still need to hit your target.

You can locate your own target if it's close enough - say 10-30 miles or so - from where you expected it to be. With a slower missile your target will have drifted a lot more.

I think taking out SAMs is huge thing. Or I am wrong?

Thrust is not the issue, the issue is net thrust. Essentially the missile/engine is compressing so much air that trying to get more air to produce more thrust doesn't work, you have to manage to increase efficiency, by increasing compression, without melting or blowing apart your engine

Once you manage to make significant net thrust making a bit more isn't that big of deal, it's really a critical point you have to pass.

Yes, that's what makes it even worse. Flying as fast as you can means you have very little reserve for velocity losses from extensive maneuvering.

> once you manage to make significant net thrust making a bit more isn't that big of deal

You’re still limited by your fuel and flight envelope. The latter which bleeds the former.

Hypersonic missiles will be harder to intercept than cruise missiles. Due to their novelty, they’ll also be harder than ballistics. (Ballistic projectiles don’t continuously illuminate their flight path. That permits for subterfuge options an air-breathing missile forfeits.)

These maneuvers are in the terminal phase. Knowing the reaction speed and the moment at which LOS is achieved as well as estimating the speed of the missile and it's acceleration one can calculate a relatively short period under which interception is possible. Outside of that there is basically no risk and thus no need for any maneuvers.

As for flight envelope we know from the X-15 that not that much is required to pull 10Gs at hypersonic speeds. There is no need for much more.

> maneuvers are in the terminal phase

One, this leaves the missile, which is screaming through the atmosphere, vulnerable in a way ballistics are not. (And visible in a way cruise missiles aren’t, either.) Two, if you have a carrier strike group in the middle of the ocean, this strongly restricts how much manoeuvring can be done. The target knows where you’re ultimately headed—if you tactfully manoeuvre into a blank patch of ocean, the strike group is fine.

> flight envelope we know from the X-15 that not that much is required to pull 10Gs at hypersonic speeds

The flight envelope restriction isn’t a structural one. If you have a known target, there is only so much manoeuvring the vehicle can aerodynamically do without slowing down to sub-scram speeds. Yes, you could supercharge the engine, but that cascades through another host of factors.

By the time that you're close enough to the strike group that you have a serious risk of seriously missing, it's already too late for the faster interceptors to be effective.

As far as only so much maneuvering you can do before being too slow for the engine, yes that's probably an issue for the HAWC, but scramjet missiles have been demonstrated to achieve Mach 9 in atmospheric flight which allows a lot of energy to bled out before you drop out below Mach 4.

They are slower than ballistic missiles, but fly more unpredictably. Ballistic missiles fly a parabolic trajectory and therefore an intercept can be calculated, whereas hypersonic missiles fly in the atmosphere at high speeds and can change their direction

> but fly more unpredictably

Ballistics cruise quietly. An RCS impulse can covertly re-aim it. Hypersonics scream bloody murder their whole flight path. Every satellite over the horizon will see it.

Hypersonic manoeuvres are, moreover, expensive. You have to deflect a lot of molecules to make small changes. That costs you in speed, fuel and time to arrival. If you need to maintain scram airspeed, your options are seriously limited.

This weapon has a place on the battlefield. But it’s not a strategic element.

They're too fast to catch up with (i.e., from behind). But if someone sprints straight into your fist, that person will be hurt even if your fist itself is fully stationary. In fact this probably makes them somewhat more vulnerable to an interceptor's warhead's shrapnel: even lesser damage, survivable for a slower target, might be much more serious for a target flying at high Mach speeds (not the mention the imminent "Columbia syndrome" of very hot air suddenly inside your vehicle).

That only works if your rate of tangential acceleration is quite low. The reason why you'd make an airbreathing hypersonic instead of a ballistic missile is so it could manoeuvre.

Your tangential acceleration is zero in a sustained flight. So it works, then.

Sure hypersonic missiles will be detectible by infrared sensors. But those sensors have limited range, narrow field of view, and don't work well through clouds. And IR sensors can't give precise range data so they're less useful for targeting interceptors.

For a moment, reading only the first paragraph, I was hopeful that the problem of accelerating from subsonic to hypersonic had been solved. Alas, further down it makes clear that a booster was involved. Presumably a small solid rocket that accelerates to Mach 3-5(?) prior to scramjet ignition. Fine for a weapons system but will never be useful as transportation.

Is anyone aware of progress toward being able to reach these speeds without disposable boosters?

The SR-71 could make Mach 3 on its own but at incredible cost in fuel and complexity.

SpaceX Starship will do this and be fully reusable. Starship can fly long distance with a reusable booster and somewhat shorter distances without a booster.

Granted, its not really 'flying' but it does reach the speed needed.

> The SR-71 could make Mach 3 on its own but at incredible cost in fuel and complexity.

the SR-71 never struck me as "incredibly complex", the space shuttle however...

The J58 powering the SR-71 is still one of the most complex engines ever built. The space shuttle is a simple rocket by comparison.

https://en.wikipedia.org/wiki/Pratt_%26_Whitney_J58

And the SR-71 is so simple the complexity falls off a cliff at the engine, hence your inclination to only care about that in comparing the two.

The space shuttle is like a reusable mobile space station, airlocks and all. Occupants of the SR-71 wore space suits the entire time, there's a lot of minimalism on display in the SR-71 which is a large part of what makes it so glorious.

You seem to be suggesting but not outright saying something that is a misconception: The SR-71 did in fact have a pressurized cockpit, which was also air conditioned as well (it had to be, because the aircraft would cook the crew otherwise.)

The SR-71 was sophisticated in other ways as well; for instance in having ejection seats. In fact the first four shuttle flights (all Columbia) had ejection seats too and guess where they got those seats from? The SR-71 of course. And on those flights with ejection seats, guess what the shuttle crew wore? They wore pressure suits, like those worn by SR-71 crew! They stopped wearing those starting with STS-5, when they removed the ejection seats. However the pressure suits (though not the ejection seats) came back after the demise of the Challenger.

What I am not saying: that the shuttle was simple.

What I am saying: That the SR-71 was more sophisticated than you've given it credit for.

I think the two of you are largely in agreement, but GP rightly points out that the SR-71 was less complex than it could have been and that this is in party why it was so successful. The ability to leave stuff out in engineering exercises can lead to substantial benefits and that's worth noticing.

The SR-71 was very complex. For example it had multiple heat exchangers to get rid of heat, to transfer it to the fuel before it was combusted. The titanium structure was complex to maintain. Welding needed to be done in "bubble" work stations under protective gas.

> The titanium structure was complex to maintain. Welding needed to be done in "bubble" work stations under protective gas

Operational complexity is orthogonal, and tends to be inversely proportional to simplicity in implementation...

For instance they needed to refuel the thing immediately upon reaching operating temperature in flight, since it leaked like a sieve on the runway until everything expanded. Rather than try fix that somehow with more engineering, they shifted the complexity into operations.

IIRC it couldn't even start its own engines cold, relying instead on hot-rod v8s setup on the runway to bootstrap the thing. More operational complexity in favor of leaving an entire subsystem out of the plane.

Don't get me wrong, I'm a huge fan of the SR-71, but so much of that appreciation stems from its ruthless pursuit of its narrow operational goals, for as much what it isn't as it is.

It's the polar opposite of stuff like the space shuttle or F-35 where the aggregate complexity is through the roof to accommodate a kitchen sink.

Oh come on. SR-71 was a complex military aircraft. Maybe it was not as complex as the space shuttle. Certainly much more complex than an F-16.

One can start here for example http://www.enginehistory.org/Convention/2014/SR-71Inlts/SR-7...

>Operational complexity is orthogonal, and tends to be inversely proportional to simplicity in implementation ...

I'm not sure what your point is with this. All complexity is operational complexity.

> All complexity is operational complexity.

Uh, what?

Example to illustrate the difference:

Automatic transmission in an automobile, operationally simpler than the manual constant-mesh trans it broadly replaced: Driver (AKA the Operator) selects drive or reverse when stationary, no need to participate in gear changing while in motion. Substantially more complex in implementation in exchange; go look at the hydraulic valve body of your average slushbox.

Manual trans: Simple implementation, single clutch assembly, sets of gears selected mechanically by axially sliding dogs on splined shafts. Operationally complex since the driver must continuously participate in the selecting of gears and clutch operation while in motion.

Oh I see it now, you mean at the time of operation by the end-user.

I was thinking about the operational complexity of developing/manufacturing such thing, hence why for me it seemed to be virtually the same thing.

Thanks for taking your time to clarify this.

The arguably most complex technology of Space Shuttle was SSME. Also, arguably the most important part of LEO rocket technology is engine - as soon as engines matured enough, space era started. Yes, there are gyros and superlight tanks, but Lambda-4S still does illustrate the importance. And hypersonic winged flight problems were greatly decreased in the Space Shuttle case by a "brute force" approach with ceramic tiles.

SSME was more or less repeated in results by RD-0120, and rather soon. I'd argue RD-0410 was more complex. SR-71 engine works in two different modes, and even today is not really repeated elsewhere. I think that shows how awesome the SR-71 design was - especially, but not only, for its time.

I'd appreciate a good analysis of design problems and solutions of SR-71 to decide which project was technically more complex.

I believe the descendant of HOTOL is intended to bridge that gap... https://www.reactionengines.co.uk/

Blackbird does 3.75 designed maximum on turbo-ramjet I think?

Check out Hermeus, working on building a reusable hypersonic aircraft. The engine they're using is a proprietary TBCC engine based on the GE J85.

Unless you're trying to go to space, there really isn't much reason to go this fast in the first place. Even relatively modest supersonic passenger flight has proven to be a commercial failure (good luck to Boom Tech inc... you guys will need it.)

If you're going to space, an SSTO with scramjets would be interesting. But I think if SpaceX's reusable Starship succeeds without that tech, it would be hard to justify the additional complexity and expense of an SSTO built with a class of engine which hardly exists at all right now.

> relatively modest supersonic passenger flight has proven to be a commercial failure

Tried it once in the 70s. Didn’t work. Everyone go home.

We tried with the British-French Concorde, the US Boeing 2707, and the Russian Tupolev Tu-144. That's three tries (or maybe two, the Boeing version was cancelled before prototype completion).

Maybe we can do better today with the lessons learnt and the advances in material science since then. There's several startups banking on that. But so far commercial supersonic flight has only worked out as prestige projects, not as commercial successes.

Wasn’t TU-144 just a pissing contest entry with retrofitted engines of another aircraft? And Boeing 2707 quickly scrapped? Only Concorde ever saw the light of commercial operations. It was truly limited by its technology, of that date. And post 9/11 situation sealed its fate, its had one fatality in 20 years, its already better than 747 max by that metric. There is no point in saying Supersonic is impossible, things changed a lot in last few years. Having computer monitors instead of a dedicated flight engineer with gazillion dials and Fly by wire, it can be much more optimised now. Boom just needs to make a working jet, and it would definitely revolutionise aviation again.

> Wasn’t TU-144 just a pissing contest entry with retrofitted engines of another aircraft?

Pissing contest, maybe, but the Tu-144 was its own aircraft. The airframe was designed from day one to be exactly what it was, a supersonic airliner (and contrary to popular myth, the design was not simply stolen from the Concorde although maybe the premise was..) I'm not sure if the original Tu-144 engines, the NK-144's, were originally intended for another plane, but as far as I know the only planes they were ever put in were the Tu-144. They were later replaced by RD-36 engines, which were designed for the Tu-144.

And let's not forget the Concorde's engines had a military background. They were derived from engines originally meant for the [cancelled] TSR-2.

The major problem I see for Boom is social. Environmental and class/economic concerns particularly; see the public backlash against Jeff Bezos' rocket hop for instance. Not to mention, the little experiment we've been running for the past ~2 years with remote work and teleconferencing has probably reduced demand for high speed business travel.

I always thought the problem was intractable and related to just ... moving through the atmosphere at that speed induces a lot of drag. Has there been any sort of major breakthrough that would change that?

I guess you could always fly at a much higher altitude (with its own problems) but it all seems motivated by, well, prestige as you put it. Like, I have a hard time believing it'll ever be more economical (as a commodity/for the market), environmentally friendly, profitable (for the operator), or just more practical than transsonic flight. The only advantage seems to be bragging rights, and the ability to cross great distances really quickly for an elite few.

> But so far commercial supersonic flight has only worked out as prestige projects, not as commercial successes.

I suspect that further optimizing the fast part of air travel doesn't offer as much gain as further optimizing the slow part, which is between the real origin and the plane door and between the plane door and the real destination.

https://en.wikipedia.org/wiki/SABRE_(rocket_engine)

I'm curious about the PR strategies at play when governments either saber-rattle or keep secrets.

Announcing breakthrough, surprising even, HAWC tech seems to clue in opponents about what sorts of countermeasures they'd want to start developing.

By contrast, the US has held the high-altitude Aurora/SR-72/whatever tech very close to the vest for decades, when it's pretty much obvious that a new generation of high altitude replacements for U-2/SR-71/etc have been in the works or operational for a long time.

Could this be economic trolling/baiting like what in the 80's, (in part?) contributed to the USSR bankrupting itself trying to keep up with cold war tech?

> contributed to the USSR bankrupting itself trying to keep up with cold war tech?

Source?

USSR was spending majority of it's GDP on mil., hard to imagine it was not a major factor.

It is probably a reference to the SDI program, also called the Starwars program. Note that the economic impact on USSR is just speculation.

https://en.m.wikipedia.org/wiki/Strategic_Defense_Initiative...

Yes, and yes that remark was speculative.

It was known as "the strategy of technology" and there's been a lot of controversy if really was as effective as many claim.

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

Given the fact that other governments are fielding hypersonic scramjet missiles, I don't think so.

> Announcing breakthrough, surprising even, HAWC tech seems to clue in opponents about what sorts of countermeasures they'd want to start developing.

It's pretty hard to hide hypersonic devices these days, and the concept is not exactly a secret: Russia and China are testing devices, and multiple other countries are working on developing their own.

Russia is not really testing devices per se anymore, they are preparing for mass production of hypersonic air breathing missiles. We don't know too much as for China.

> they are preparing for mass production of hypersonic air breathing missiles

...or so they say. Of course they've been preparing for mass production of T-14 and Su-57 for quite some time now. Any day now they'll get them, I'm sure...

T-14 is ready for mass production, it's just too expensive for the broke Russian government to buy enough of them.

3M22 unlike Su-57 has actually achieved it's goals. It has already been fired from ships and hit targets while achieving it's speed and altitude goals. Su-57 has not been able to achieve it's goals of being stealthy or being reliable so there is no reason it would be readied for mass production.

If I remember correctly it was claimed that the Su57 was too good and that's why they we're cancelling serial production.

> We don't know too much as for China https://en.wikipedia.org/wiki/DF-ZF

Hypersonics aren’t new tech, they were tested and developed decades ago by the US. It’s only recently that they’ve made a reappearance. Why do you think it took only 2 years for multiple military branches to spin up and test multiple separate missile designs? I would argue that Russia/China are playing the PR game in order for the US to appear behind in terms of missile technology.

There are offensive weapons that you advertise so that the enemy wastes resources to defend against.

Having nukes for MAD is useless if no one knows you have a credible threat.

"Of course, the whole point of a Doomsday Machine is lost, if you keep it a secret!"

I sorta suspect that this is more about the fact that the US knows this isn't a secret to China and Russia, so they're using it as an opportunity to brag domestically and get more funding.

MAD worked out pretty well. Sometimes the best outcome of a weapon system is that it's never used.

Reminds me of the Doomsday Machine in Dr. Strangelove.

> The Whole Point of the Doomsday Machine is Lost if You Keep it a Secret!

How a such hypersonic missile locks a target? Does it use a radar or some optic system? I guess that plasma around the body might disrupt conventional guiding systems.

For blunt-body spacecraft, ionization starts at around Mach 10. The aerodynamics of a missile will be different of course. Regardless, there is headroom above the Mach 5 hypersonic threshold before blackout occurs.

Ionization applies starting at a given frequency depending on heat. You have to reduce the heat around the radar or move the radar somewhere where the air is less hot. You also have to use a radar of a higher frequency.

All actually deployed systems are nuclear capable, for them aiming is not a huge concern because the boom is very big.

What the US is playing at with their strictly conventional warheads is anyone's guess, the overall impression is a of a "we want that toy too!" program.

Seeker window design is a whole branch of missile engineering.

Most missles use a quartz window that is sprayed with an evaporative coolant. In more advanced designs the coolant flows through microchannels and then out micro holes on the leading edge, where the coolant evaporates and provides a film cooling.

https://www.spiedigitallibrary.org/conference-proceedings-of...

Is it just me or has the Pentagon and the complex largely replaced the word "soldier" with "warfighter"? Feel like I've seen it a lot lately and I'm not sure what the change implies

Good call. Seems unnecessary, like the slow transformation of “emergency room “which used to be known as the ER to “emergency department“.

In fairness, emergency department is more sensible. They generally aren't a single room.

Soldier to warfighter seems unnecessary.

EDIT: It seems possibly using "warfighter" is more accurate as marines and pilots aren't soldiers?

Sure but then you get into the situation where even though the full name is Emergency Department they still refer to it as the ER and not the ED.

That's just a bit of lag though. ED is becoming increasingly common.

Army has soldiers, Navy has Seamen/sailors, Air Force has airmen, Marines has marines, coast guard has coast guardsmen.

Well for one US citizens might have to quarter warfighters.

It simply means that marines, sailors, etc get bent out of shape when you call them "soldiers." In their lingo, soldiers are in the Army.

In common parlance, a 'soldier' is anybody who is part of a military and an 'army' is any and all military. But I would not expect the Pentagon to be so casual with their use of terms relating directly to their affairs.

The common parlance is just wrong. Soldiers do not serve on ships

Language and vernacular are fluid and things can become new things.

The people who serve on ships can become soldiers by consensus.

But Navy personnel were deployed to Iraq and landlocked Afghanistan so clearly the DoD doesn’t see the clear delineation.

Huh, in my country, we just say "personnel". Covers all genders, all branches, and territorials (our version of the National Guard, I guess) as well as the regular force.

> replaced the word "soldier" with "warfighter"

Technically, only the Army has soldiers. The non-exclusionary term used to be “men and women in uniform,” but that got tired, so I guess we get “warfighters” now.

Yeah, Marines particularly don’t like being called “soldier”, they’re not soldiers they’re Marines. Probably same for the Navy, Air Force, Coast Guard, CIA operatives, etc. The civilian executive branch probably had a headache over that, and just started using the catchall term warfighter to refer to them all.

We also have "serviceperson", but you can't sell Call of Duty games that way.

The one fps game that contained "warfighter" wasn't call of duty. https://en.wikipedia.org/wiki/Medal_of_Honor%3A_Warfighter

Did not know about the usage of soldier, thank you.

I assume someone thought it sounds cooler and will help them recruit. It's an awful term, although maybe it will make it slightly harder for people to claim that the US military is a force for good because "our warfighters are global peacekeepers". Really highlights the absurdity.

It is politicians that keep insisting the job of the army is to get Afghanis to read and adopt liberal values.

Peacekeeping is not popular in the army, for good reason. They are there to fight wars, not deliver social programs, build nations, or referee conflicts.

If using language like "warfighter" can get the politicians to lay off on using the army for things other than fighting wars, then the clumsiness of the phrase is worth it.

I suspect, though, that this is just more corporate-speak infiltrating the military bureaucracy.

There ought to be a branch of the military that is dedicated to those goals.

I can imagine there are a lot of people who might be interested in that, but not in the war fighting. Today those people either don't enlist, or enlist and hate that aspect.

Not the military, that's what the State Department is for. Or the UN.

Edit: Ok maybe not what it's for, but the State Department is a better fit. Nobody is ever going to trust a foreign military to do anything good in their country.

There are many NGOs that work to spread liberal democracy, and the US government has the Peace Corps.

I think it is for recruitment. For me the word soldier makes me think of someone who is unempowered. Just another pawn on the table, getting their balls busted by their senior officer for not shining their boots enough.

Warfighter makes me think of someone who is empowered. A warrior willingly testing themselves in the harshest conditions imaginable. Fighting against adversity. Not submitting to it.

Your post reminded me of all the videos I watched on this subject. The ridiculousness of it all. A group of marines in Afghanistan who in the process of trying to deliver security to a village end up outside of it on a vantage point, ordering artillery shelling of the same village they are tasked with protecting because tabliban started firing mortars at them from within the village walls.[0]

[0] https://youtu.be/ZvZj3u1Eenw?t=2684

If you want peace, prepare for war.

War fighter showed up to replace soldier about the same time the space force was announced.

It's meant to be a blanket term to satisfy categorization from rifle carrying traditional soldiers to drone pilots in an Idaho parking lot.

No, I heard this in 2002 by our marketing guy who was in communication with people in the military bureaucracy (of course to sell them our products).

At least for DARPA this change was well established even 26 years ago. It’s a way to be more inclusive of various roles within the military.

There's also been a major push to use the word "warrior". Not everyone is a fan.

See, eg: https://foreignpolicy.com/2021/04/19/united-states-afghanist...

Edit: As others have noted, "soldier" is traditionally a term reserved for members of an army. So for anything that cuts across the entire armed forces, you end up with soldiers, sailors, marines, airmen, coast guardsmen, and (of course) guardians (which is, I'm sad to say, the actual term for members of the Space Force). That's unworkably long (and it gets worse if you want to try and find gender neutral phrasing for "airmen" and "coast guardmen"; "airmen, airwomen, coast guardsmen, coast guardwomen" is even more ridiculously unworkable, and "airperson" is just too dumb to contemplate). I think the only reasonable answer is "serviceperson" or "servicemen and servicewomen", but I can't fault people for disliking those. But "warrior", as the article notes, already has incompatible meanings, and "warfighter" isn't much better.

Maybe the real answer is just to adopt the Space Force term for the entire armed forces, and call everyone guardians. (And it kills me that this is, actually, one the better ideas I've heard.)

"Goals of the mission were: vehicle integration and release sequence, safe separation from the launch aircraft, booster ignition and boost, booster separation and engine ignition, and cruise. All primary test objectives were met."

When the booster separation occurs, what happens to that booster? Does it self destruct on the way back down? Would any part of it be recoverable by inquisitive minds? Is booster tech so rudimentary that no secrets would be lost if recoverable?

"and cruise...met" does that mean it just essentially flew in a straight-ish line? seems like guidance would be important. walking before running?

These absurd speeds result in a significant amount of aerodynamic heating, so assuming the booster is simply not shielded much it'll likely disintegrate in seconds after being detached and no longer in the missile's shadow.

>> released from an aircraft seconds before its Northrop Grumman scramjet (supersonic combustion ramjet) engine kicked on.

No. The scramjet would only work at supersonic speeds. The missile was boosted to speed/altitude by another conventional rocket before lighting the scramjet.

>> The HAWC vehicle operates best in oxygen-rich atmosphere

As opposed to a oxygen-poor atmosphere? Mars? Venus? And "best" suggests that this missile might operate poorly, but operate nevertheless, in some other non-oxygen place. Maybe this thing also travels through space. We may be going to war on Venus after all.

> As opposed to a oxygen-poor atmosphere?

My interpretation of that sentence is that it performs better at lower altitudes, where the density of oxygen (and the other atmospheric gases as a whole) is higher.

This is an instance where I think the domain (.mil) explains it pretty well. "Warfighter" and "warfighting" have been fairly common vernacular in the literature for awhile in the same way many fields have specialized jargon that may be largely synonymous with more common word choices. If it's unfamiliar it's probably because most people don't read military literature (despite often having strong opinions on military activity).

I'm surprised it uses a hydrocarbon fuel. I thought that scramjets pretty much had to use pure hydrogen to keep the flame front fast enough to maintain ignition.

Isn’t the point of these you can launch them from Kansas while at the office and they still reach their target in a matter of minutes? No huge deployment required to get a missile boat in range, just load in the coordinates, press the btn, and go back to lunch.

This is part of the conventional prompt global strike initiative. Hypersonic weapons will eventually be deployed on land, ships, and aircraft.

https://news.usni.org/2020/02/18/navy-confirms-global-strike...

For comparison: https://en.wikipedia.org/wiki/P-800_Oniks

The better comparison would be : https://en.wikipedia.org/wiki/3M22_Zircon

Are we a step further and closer to accidental war?

Russia already has one alleged, proven? IDK.

Our response time to decide is getting shorter and shorter.

So, hence it will be up to AI combined with Humans.

I don't understand the purpose of having a missile that fast.

More speed = more difficult to both intercept and detect (less response time).

Not sure what the commercial applications would be though.

Nothing can shoot it down (yet).

Missile interception technology like aegis relies on other ships detection and coordination with onboard defenses in an aegis fleet network.

Faster missiles mean a solution may be coordinated or countermeasure plotted too slowly to have any effect, or to arm things like CIWS countermeasures.

hypersonics, simply put, can sink US aircraft carriers before their protective fleet can take action, effectively neutralizing US presence in a region.

> hypersonics, simply put, can sink US aircraft carriers before their protective fleet can take action

Hypersonic missions are slower than ballistic missiles. Their advantage isn’t speed per se, but in being able to fly under the horizon for longer. They’re also more manoeuvrable, though at those airspeeds you’re somewhat limited in this domain.

Mach 5 is a bit faster than the Virgin Galactic flight (Mach 3). The folks on Inspiration reached ~ Mach 23.

> Mach 5 is a bit faster than the Virgin Galactic flight (Mach 3)

Mach 5 is a lot faster than Mach 3, not only in relative terms (it's 40% faster) but in absolute terms as well: around mach 5 is a regime change where the physics of flight get altered and interference effects become extremely significant, small changes to any surface component will have major impact on airflow, and thus will affect any component downstream from them.

This makes air-breathing hypersonic devices a much bigger challenge than air-breathing supersonic ones.

> This makes air-breathing hypersonic devices a much bigger challenge than air-breathing supersonic ones.

Indeed, and the Virgin Galactic vehicle isn't even either of those; it uses a hybrid rocket engine instead of breathing air. Hybrid rocket engines are fairly simple compared to liquid fueled rocket engines and are fairly safe compared to solid fuel rocket engines (although the fatal V.G. explosion some years ago should perhaps challenge this wisdom?) However they're probably a dead end technology and I don't think V.G. will ever get to orbit with them.

DARPA has such a list of impressive, world wide useful technologies that wouldn't have been able to be created without funding from the government at the time given the time and money and at time, unlikeliness to be successful [0].

It really sucks that there's a 'D' for 'Defense' at the front of the acronym. Their website says they're "creating breakthrough technologies and capabilities for national security". Horrible that national security is the reason for this, when it should be human progress.

[0] https://www.itpro.com/technology/34730/10-amazing-darpa-inve... [1] https://www.darpa.mil/

Many humans are quite aggressive. Pacifists are easily defeated by force. How can you have progress without security?

That's a straw man. The problem is tons of research and development won't happen without the state, but the main avenue the state funds development (as opposed to research) is the military.

There are many possible futures, and the world is highly non-ergodic, so there is a real cost here to biasing the development of technology in this matter. "Opportunity cost" doesn't do the concept justice.

We don't have to stop military research, but we should bring up the Arpa-E and other such things to bring balance to the situation.

> That's a straw man. The problem is tons of research and development won't happen without the state, but the main avenue the state funds development (as opposed to research) is the military.

The reason the op's comment is not actually a straw man (https://en.wikipedia.org/wiki/Straw_man) is because the first governments were developed out of a necessity to ensure a unity of peoples, the functioning of essential systems, and the protection of said peoples and systems. It's also why (for instance) the very first sentence of the US constitution has multiple touch points with national security:

> We the People of the United States, in Order to form a more perfect Union, *establish Justice, insure domestic Tranquility, provide for the common defence, promote the general Welfare, and secure the Blessings of Liberty* to ourselves and our Posterity, do ordain and establish this Constitution for the United States of America.

To summarize: defense is how so much of our monetarily non-viable societal advances take place because defense is primarily why governments exist at all. Even arpa-e (thanks for your edit—it's a good topic to bring up) exists to minimize our reliance on foreign energy, which is directly motivated by national security.

Come on, nobody knows how the first governments were developed. No written records exist.

Yeah, and as far as we can tell those first states massively sucked for almost everyone, too.

We know what government is per se, regardless of the motives of the earliest state governments.

But here we miss an important point which is that government is natural to human societies. The mistake is to think that government is some artificial construct at odds with human nature. Tribes are governed. Families, the smallest society, are governed. What we call "government" is just a modification of the most basic form of government of the family (kings, for example, were analogically fathers of the kingdom). The authority of the state is derived from the authority of parents through the principle of subsidiary.

I agree with the spirit, but I prefer to reject the natural/artificial distinction. Societal and biological evolution can be a very "arbitrary" processes. Sometimes something just happens, and is good enough, and sticks around. It's ultimately pretty subjective which things are "over-determined" and what wasn't (photosynthesis? agriculture? Something like eukaryotes from endo-symbiosis?), without being able to run a bunch of difficult experiments.

Government and money are two institutions who's origins are much debated, but I would be find replacing them with something else, "self-perpetuation" replaces "natural" for me.

I also so think this is dovetails with the best argument for reproducible bootstraps (as the follow up to reproducible builds). Without that, and like with our socials institutions, we have a a "historical bootstrap" we are constrained by. But by making an artificial bootstrap, we gain some freedom to tinker rather than being completely constrained by historical happenstance.

With software it is clear what this looks like. With something like governance and money it is less clear. Certainly it's hard to imagine the John Locke style arguments bootstrapping from "primitive man" working out, as children must be raised in a culture before they get the privileges of democracy, and are thus biased. But perhaps there are other more feasible ways.

America is preventing Russia from antagonizing Europe, all the while we foot the bill for maintaining a capable military.

China is a looming threat. If you don't see that, I don't know what I can say.

Take away America's military and see what happens.

Tibet, Hong Kong, Taiwan, Spratleys, 9-dash, water rights, Belt+Road indebtedness, Crimea, Ukraine...

The US has to be strong out of necessity, and we get treated like shit for it. America is far from perfect, but it's Democratic and celebrates individualism and free speech. And I'm not persecuted for being LGBT. I'd hate to be in Russia or China where I'm told I can't think my own thoughts or have my own preferences.

If we didn't have to pay so much for our military capabilities, maybe we'd all get to enjoy the same free health care and social programs that Europe, Canada, and other nations enjoy.

Europe needs to carry some of this weight.

> America is preventing Russia from antagonizing Europe?

Er, Ukraine is in Europe. Out of 10, how would you rate the USA's efforts at stopping Russia there so far?

"Europe" is probably the wrong term here. The USA's efforts to stop Russia from antagonizing NATO members probably rates 8/10.

Part of Russia is also in Europe.

No, no.

Ukraine paid the 'entry price' that was asked of them to be protected by USA, (and France, UK, Russia, China) by surrendering their nuclear weapons.

This was a level of vulnerability and trust in third parties the good citizens of USA (and the others above) would never for a second countenance.

The USA (and the others) willingly signed up to the deal [1]. And then failed to do any deterring when it was time to walk the talk.

[1] See https://en.wikipedia.org/wiki/Budapest_Memorandum_on_Securit...

That was a non-binding memo. If Ukraine wanted protection then they should have insisted on a mutual defense and non-aggression treaty.

> That was a non-binding memo.

That's not the problem of Ukraine. The whole world sees what agreements like that are worth. Alternatively, if that would be the binding memo, and USA broke the "legally binding" promise, nobody would prosecute. The reaction of the world would be about the same.

Bottom line: non-bindingness doesn't matter here.

>Part of Russia is also in Europe.

Care to explain?

Edit: sorry, my brain read Europe as EU.

The cat is out of the bag, Ukraine gave up 3d largest Nuclear arsenal on the promise that other nuclear powers mainly US would provide security. Everyone saw how that played out so a country would need to be suicidal not to start a nuclear program.

Just ask Gadhafi, Saddam and Kim Jung Un. Oh, right, only one can answer!

Ukraine did not have as much of a choice as one would think. All the nukes were set up to be controlled by Moscow and it would have taken enough time to bypass the controls that the Russian army could feasibly have invaded or destroyed them.

They were not a major portion of Nuclear Weapons R&D and manufacturing were done in Ukraine including design and manufacture of majority of electronics including guidance systems, comms etc. as well as most top tear weapons were designed by Yuzhnoye Design Office (Dnepr Ukraine) and manufactured by Yuzhny Machine-Building Plant (Dnepr Ukraine)

Ukraine indeed had a lot of manufacturing and design of nuclear weapons. Even then the control, launch and timings were all centralized in Moscow. They would have had to reverse engineer and hack a lot of it amidst attacks from Russia and perhaps even the US.

I think you are still confused the control systems were designed and manufactured in Ukraine there was nothing to reverse eng. The only step not done in Ukraine was uranium enrichment.

Ukraine never really possessed nuclear arsenal. There were nuclear weapons on their territory but they lacked full operational capability to employ them, and didn't have the technical infrastructure to maintain them without Russian support. Those capabilities could have been built out in time but it would have required significant resources.

Right casuse Yuzhny Machine-Building Plant and Yuzhnoye Design Office are not in Dnepr Ukraine.

> Ukraine gave up 3d largest Nuclear arsenal on the promise that other nuclear powers mainly US would provide security

> mainly US

You missing historical order here. Ukraine gave up their arsenal long before they decided to drop Russia as an ally and play with Europe/USA (latter happens after "Maidan"). So at given time point (when Ukraine signs memorandum) they done it with _only_ Russia' protection in mind (as there was single country in past and they're both slavic)

Please enlighten me on the order :) being a Ukrainian born in 70th

Citing nti.org:

> By 1996, Ukraine transferred all Soviet-era strategic warheads to Russia.

> Ukraine received extensive assistance to dismantle ICBMs, ICBM silos, heavy bombers, and cruise missiles from the __U.S.__ funded Cooperative Threat Reduction Program

Citing wiki: > Euromaidan was a wave of demonstrations and civil unrest in Ukraine, which began on the night of __21 November 2013__ with public protests in Maidan Nezalezhnosti (Independence Square) in Kyiv

Easy, uh?

well even by your convoluted logic you would have to go back to Orange revolution in 2004. But none of what you site has anything to do with Russia being considered a mil ally. by Ukrainan gov. Russia was considered the biggest threat to Ukraine independence starting with Ukraine's first president.

> convoluted logic

The only convoluted thing here is your own history as you see it.

> Russia was considered the biggest threat to Ukraine independence starting with Kyivan Rus'

Until Yushchenko there was no such president. Relations never were stable, though.

Look at A.I. Kuzmuk paper "Ukraine military doctrine evolution" if curious. VDU-1993 and VDU-2004 never considered Russia as a threat. VDU-2004 states there is no direct military threat against Ukraine, just possibility of being involved into bigger conflict. Kuchma even cancelled statement about NATO integration in VDU-2004, by making it more smooth.

I highly doubt Kuzmuk ever read that book to begin with :) He certainly never wrote it :). To argue an empire is not a threat to the country that gained independence from it in very recent time is very toll order and Kravchuk always aknowleged Russia as a threat to Ukrainian independence as did Kuchma.

Well could you point to the downside of this? From teflon to internet and countless other things you use every day that came out of DARPA and other def. research, what would have changed if it was funded via different model?

History shows that conflict has actually been rather useful for our development

That's circular — it's important precisely because nothing else created the political will for that much state-run development.

We should at least try to do non-military development, even if military dev will continue to have an edge.

The problem is privileging technologies that have defence capabilities. There are likely countless ideas that could have similar success to DARPA projects if they had similar access to capital and state support.

However, unless it can show off some military capability its funding can't be justified using the current model, leaving a gigantic subsections of technologies that could have similar innovative impact underserved by this level of support.

Without defense, the others cannot exist. Without defense, you cannot have a space within which you can securely do other work. So it cannot be a matter of competition but prioritization.

Of course, we can criticize the massive amount of funding that goes to military contractors and the like (Eisenhower did). That's where the devil is: the military-industrial complex.

"Defense" is the worst euphemism for the military. I wish it was still called the Department of War, which is honest.

No one is saying abolish the military. In in fact we are saying some forms of state–military complexes might be good.

It's the idea the state-driven industry must be tied to defense and not anything else that's the problem.

I think the complaint is not that the government funds research for defense, it's that it could be funding energy, medical, etc research.

I honestly don't know if I fully agree with his complaint, because I'm fairly sure the government does fund a lot of other research that isn't defense focused (see a lot of universities).

It funds many sorts of research but much less development. Research ideas do not develop themselves and so the story of modern academia is zillions of abandoned ideas.

DARPA does lots of good things — I have in fact worked on a DARPA project and enjoyed it. It's well run.

But each of those things has to be contorted to have a military purpose, even if the main benefit we get in the end is not military-related.

We should be able to research those things just because they are good, without laundering their best purpose. And we should open the door to other things that seem just as promising, but are harder to so launder.

The fact I can't tell you the counterfactual is kind of the point — most of us have no idea about the world-changing effects of the development not persued might be, just as the average person on the 1970s did not envision today's internet. The world of possible futures is simply too open ended.

One prominent one is that we use fear to control other countries instead of love.

We spend so much human talent on defense, and sure we got a bunch of great technologies, but who's to say that we wouldn't have got them through some other avenue, later? Or perhaps even better technologies. I only speculate about the former, but I am quite certain a lot of the violence in the world has been caused by American Neo-colonialism and the terrorism we imposed upon the world. I am a betting man, and I bet that if we didn't fuck the Russians over so hard in WW2, that we wouldn't have had the cold war.

How did the US fuck over Russia in WWII? And are you aware of the billions of foreign aid many countries get from the US which is tied to issues like human rights, freedom, and democracy?

The US let the Russians break themselves fighting the Eastern front while they invaded north Africa. The North African front was basically secure while Stalingrad was happening, and if the US applied more pressure to Germany in this period, as the Russian requested, the Germans probably would not have done so much population damage to Russia.

Bitterness of this fueled a lot of ideological tensions. I was also taught that a large motivation of dropping the Bomb was to scare the Russians.

Source: My Highschool education. Obviously, commentary on WWII is not objective, but I stand by my thesis, considering the actual action that the United States engages in in present times. Its in our history to be both ideologically driven and meta gamers.

That line of argument doesn't make any sense to me. The Americans were actually in FAVOR of a cross-channel invasion in 1942-43 (see operation sledgehammer and operation roundup), but were shouted down by the British. Which, to their credit, was fair: the Allies lacked the ability to launch a large amphibious assault in 1942 into France. They lacked a sufficient fleet of landing craft, along with the proper doctrine, the same degree of air superiority they would have in 1944.

"The North African front was basically secure while Stalingrad was happening"

That doesn't make any sense. Operation Torch (the Allied invasion of Morocco and Algeria) didn't even start until Nov 8th, and Montgomery's position in Libya was hardly "secure" before November. But the Soviets were already launching counter-offensives and encircling the German army by the end of November. If you're counting from the beginning of the main Stalingrad offensives, August 1942, yeah maybe you could call the North African theater "stable", if by stable you mean that the Allies just one a defensive victory and managed to stall out an offensive into Egypt. But it's not like they could cancel their planned invasion of Algeria and Morocco and re-plan for an invasion of France in a couple months.

Plus the US would be invading mainland Europe Sept 3rd of 1943, and I really don't think they could have performed a successful invasion anytime sooner.

It’s hard to imagine the scale of the U.S. air operations against Germany and say the U.S. let the Russians break themselves without doing anything to help. Or look at the disaster that was Market Garden and think the U.S. could have invaded earlier. The U.S. was under no ethical obligation to throw away lives uselessly in a German blender as a distraction.

Without Lend Lease keeping the Russians supplied with food/logistics they would have starved and collapsed.

Straw Man noun 1. an intentionally misrepresented proposition that is set up because it is easier to defeat than an opponent's real argument.

My comment speaks directly to to above post as follows: "It really sucks that there's a 'D' for 'Defense' at the front of the acronym. Their website says they're "creating breakthrough technologies and capabilities for national security". Horrible that national security is the reason for this, when it should be human progress."

As for the world being difficult to predict, or to use your phrasing "non-ergodic", it is in fact easy to predict that security will be necessary. It is difficult to predict exactly what the threat to security will be. This uncertainty alone justifies development. Also, DARPA tech is well known for spreading outside of it originally intended remit. Ie the research itself can be of use in other areas.

Just assume its technologists that wanted to trick Congress into giving them free money

You know you can get entire new agencies created for yourself by the same lobbying process that private sector uses for laws that benefit them

Human progress can be itself a trap too, but often we can only tell how history rolls out in retrospect.

I suspect you know this but it was ARPA until 1972: https://www.darpa.mil/about-us/timeline/arpa-name-change

There are also IARPA[1] and ARPA-E[2] (and few others as well). ARPA-E is more "peaceful" agency.

[1] https://www.iarpa.gov/index.php/research-programs

[2] https://arpa-e.energy.gov/

Have they produced any breakthroughs?

IARPA has produced quite a few:

- https://arstechnica.com/science/2010/12/sciences-breakthroug...

- https://web.archive.org/web/20160312133713/http://www.deltek...

- https://www.scientificamerican.com/article/the-u-s-governmen...

Those are just recent, unclassified ones.

ARPA-E being the "peaceful industry" is a lot more open about private partnerships and generally just funds and provides oversight: https://web.archive.org/web/20100527161846/http://www.energy...

Some renewable fuel projects: https://arpa-e.energy.gov/news-and-media/blog-posts/refuelin...

They're focused on renewables, lessening waste, etc. and have made some contributions in that space, just not as sexy as "borgsects" and "space lasers" like DARPA or advancing nation state surveillance and electronic warfare capabilities like IARPA.

Everything is starting to get an ARPA though because of how it's somewhat allowed to cut through red tape for innovation which is hard for usgov: https://www.nature.com/articles/d41586-021-01878-z

> Horrible that national security is the reason for this, when it should be human progress.

I don't understand the point of comments like this.

Are you lamenting that human beings are such that such defense programs are necessary? Okay, I can sympathize with the general sentiment, but it's weird bringing that up in this specific context, especially since the tech in question is defensive. Yes, the need for defense is an unfortunate necessity given the reality of the world. No sense in pretending we can achieve some world where defense is not needed (we can of course try to cultivate cooperation and peace, but these are delicate arrangements that are constantly in flux). The most dangerous belief is believing you can achieve this utopian peace on earth because it makes you defenseless.

Not to be a Debbie Downer, but functional Scramjet technology does very little for humanity outside of defense. As is the case with most of what DARPA funds, no? If that wasn't the case, then the market itself would be chasing the technology. Like, what would this be useful for?

I guess I'm just fundamentally questioning what you mean when you say 'human progress'. I assume you mean it more in terms of improvement as opposed to preservation, but given the fact that life itself is a struggle against entropy on all levels, preservation is a very important foundation on which to build.

Shrinking the world would be a good use of it if we could get it to work for commercial air travel (and if we solve the sonic boom problem, but that's another issue a different part of government is working on)

The faster you go and the further you go, the more energy you use. We have limited resources and these technologies damage our planet.

It's very hard for me to imagine a world in which scramjet technology is both useful for commercial travel, and impossible to develop without massive government funding. It seems to me like technology needs to reach a point that it can be developed entirely commercially before it can be made safely and consistently enough enough for commercial passengers.

Take rockets for instance. Technology had to catch up to make them commercially viable to develop before they were commercially viable to operate.

pretty much all of air travel had direct government subsidy in the form of postal contracts in its early days and later price controls. automakers also had a huge subsidy in the form of the massive capital expenditure on highways that were free to use.

developing technologies at taxpayer expense for strategic purposes is nothing new. if private airlines were left to their own devices we probably won't ever move away from the basic shape of subsonic, fossil-fueled jet travel. as it is, the airplane manufacturer duopoly is half kept afloat by defense spending, and it remains to be seen whether or not the full financial cost of 737MAX will result in requiring taxpayer bailout.

But afaik all the airplanes used for the earliest demonstrations of airmail were privately funded/constructed. The minimum viable airplane for airmail was within grasp of skilled fabricators working out of their garages; the big government contracts came later. This is world's apart from scramjet tech.

What about the ARPAnet? That seemed to have found several applications outside of national defense.

I would argue that in order to make great progress a nation needs great security.

> It really sucks that there's a 'D' for 'Defense' at the front of the acronym.

Time for a new euphemism? The U.S. Department of Defense was called the U.S. Department of War until the end of the 1940s. Maybe this time we can call it the Department of Peace since defense apparently doesn't sound so good to people anymore.

PSA: Before posting comments decrying military spending, please recall that our species now exists perpetually under threat of Mutually Assured Destruction from nuclear weapons hanging overhead.

Your entire way of life is predicated on this fact.

Life has been good for so long that many people don't think about this.

Power balances, allegiances, resource distribution, and entire economies are shifting. This is the real game. It's not about which smartphone supplier sells the most units. It's about projection of power to secure trade, resources, and national interests.

The relative comfort of the post cold war era may not be perpetual. Our little Instagram dopamine bubbles divorce us from the cold, uncaring reality.

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