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Military Aircraft Hit Mach 20 Before Ocean Crash, DARPA Says (space.com)
80 points by Shalle on March 28, 2013 | hide | past | favorite | 81 comments


August 18th, 2011? Possibly a few tests after this have already happened?

Edit: Looks like no third flight yet. Found this followup: http://www.darpa.mil/threeColumn.aspx?pageid=2147485247

Also found this paragraph to be interesting:

“The initial shockwave disturbances experienced during second flight, from which the vehicle was able to recover and continue controlled flight, exceeded by more than 100 times what the vehicle was designed to withstand,” said DARPA Acting Director, Kaigham J. Gabriel.


And this: "[G]radual wearing away of the vehicle’s skin as it reached stress tolerance limits was expected. However, larger than anticipated portions of the vehicle’s skin peeled from the aerostructure."

And, dated: April 20, 2012


The "gradual wearing of the vehicle's skin" is called is called ablation.

Its a standard way both hyper sonic and reentry vehicles manage heat. Basically the skin boils off creating a pressure wave that the vehicle flights behind.

Wikipedia has a good description of it. http://en.wikipedia.org/wiki/Atmospheric_reentry#Ablative


Depending on what kind of impact angle they can achieve they may not need to add high explosives to this. Mach 20 is 400 times the kinetic energy of mach 1 and 40,000x the kinetic energy of a 76mph collision. So, even a 100lb craft = 1,000 times the impact energy of a 4,000lb truck at highway speeds.


For the curious: this is what railguns do. There are no explosives, just a projectile going very, very fast.


This is what all guns do.


Mortars might, but not artillery, including Naval artillery. The gun fires a shell, not a bullet, which can be designed to cause different types of damage upon whatever it hits e.g. High Explosives to blow stuff up, Armor Piercing to penetrate through armor plating before detonating its minimal explosive load, etc.

The U.S. Navy had mostly moved away from Naval artillery due to the rise of guided missiles with their much longer range, but they are investigating railgun systems which may give advantages compared to missiles.


Interesting perspective...I hadnt even thought of the possibility.


Kinetic Bombardment has been a sci-fi concept for decades, and it's interesting to see a real, possibly cost effective, technology that could make it real. At those speeds, you don't need explosives, just a lot of mass to slam into something.


According to project Thor, it would not be that cost efficient. The wikipedia page states that the rods would need to be at around 8 tons. A ton of tungsten is around 50k$ so 8 tons is rather negligible. What is very expensive is to get 8 tons of material to space. During the space shuttles era, bringing a kilogram of matter to space would cost around 20k$. A ton is 907 kilograms.

8 x 907 x 20 000 = 145M$ per payload.

I don't have the exact numbers for the cost of an ICMB with a nuclear warhead but I'm pretty sure that it is less than that. We also didn't factor in the cost of maintaining an orbital launcher, possibly manning that thing and other costs which being in space incur.

Maybe with newer launch methods bringing goods to space will be cheaper, but I don't think we'll see this kind of tech unless costs decrease to around 2000$/kg to space (1/10th of what it is now).

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


> As of March 2013, Falcon Heavy launch costs are below $1,000 per pound ($2,200/kg) to low-Earth orbit when the launch vehicle is transporting its maximum delivered cargo weight.

http://en.wikipedia.org/wiki/Falcon_Heavy


Silly question, but would it be cheaper to bring mass from space?


Well we are reaching an age (of asteroid mining) where it's probably more cost efficient to manufacture in space and ship (or railgun, I guess) the mass to earth. Probably not for a while, but I don't think it's science fiction anymore.


That gives me an interesting idea. Do you think it could be feasible to mine ore from space and then drop-ship it to some low-depth (a few hundred feet at most) part of the ocean? The heat from re-entry would likely turn the metal into a molten blob, and the sea water would rapidly cool it.


Can they guide things that accurately without assisting it mid-flight? If so, that's a cool idea, dunno if it's actually practical.



meteors!


It can't go Mach 20 in the atmosphere, so that wouldn't work.


A Thor style pure kinetic weapon was supposed to impact at around Mach 10, but this is a scram jet and as such should be able to maintain a significantly higher speed. Granted it's unlikely to maintain that at sea level, but it sounds like it impacted the water reasonably intact and so could probably do a powered dive. Also, around mach 9 is the break-even point where high explosives have more kinetic energy than chemical energy so even if it hit's at say mach 12 that's still a lot of energy.


>HTV-2 is part of an advanced weapons program called Conventional Prompt Global Strike, which is working to develop systems to reach an enemy target anywhere in the world within one hour

They're getting really close. Mach 20 is about an hour and a half to the opposite point on Earth.


Station a few of these in different locations and they're already there.


I read this too, but my first thought was "if this had been Iran we would have invaded at midnight".

Its cool tech, yes, but really...


Of course and that would've been the sensible thing to do. As Americans, we want a world where the U.S. is the one that has this technology, not countries who aren't the U.S. Our standard of living (1/4 of the world's resources for 5% of the world's population) literally depends on that state of affairs.


The US doesn't need military dominance to have 1/4 of the world's consumption. It needs to be able to pay people who have 1/4 of the world's production enough that they sell it to us. And about 80% of that latter group are Americans anyway.


That works until the country that does have military dominance decides to conquer you and take that production for itself. The market is meaningless when force can be used to take what you can't purchase in the market.

It is possible to be a wealthy nation that doesn't have military dominance (Switzerland, etc). The key is to be overall small enough that you can consume a lot per capita but still fly under the radar of the big boys. A country as big as the U.S. doesn't really have that choice.


Okay, I think I misread you. The meme of "the US only has 5% of the world people but consumes 25% of the world's resources!" is usually said by people who think it's "unfair" that the US is consuming "so much."

If you are saying that the US needs military dominance because we need to protect our own domestic production from invasion, that's something else. I still disagree but not as forcefully as I would to the other characterization.

(If an invader tried to invade America for the purpose of seizing our wealth, much of it would evaporate instantly. They can capture factories but more and more of it is IP that a potential invader could just stay home and pirate instead.)


I have no problem with the U.S. consuming that much, but I don't think we could do it without American military hegemony (and I don't think Europe could do it without American military hegemony).


I struggle with the "could not do it without military hegemony". I think the issue is military. Coca-cola achieved significant domination of world markets after WWII by piggy-backing on the distribution channels of the US Army. (essentially the troops were given morale boosting shipments of coke, later bottling agreements were put in place)

So it is reasonable to argue that Coke has achieved its position on the back of The American Military, but not reasonable to say it achieved it because of US military action.

An awful lot of US influence is down to pure dollar spend, which mostly comes through military related channels.

Is the US' international reach down to its military, or its money?

I would argue that had the last 50 years seen a global spend by the US Forestry Commission equal to that of the US military-industrial complex, then we would see Occupy! marches burning effigies of Yogi Bear.


>>So it is reasonable to argue that Coke has achieved its position on the back of The American Military, but not reasonable to say it achieved it because of US military action.

it's more reasonable to assume that Coca-Cola made most of its money by creating local factories in developing nations which struggled with getting clean water.

This pushed the use of Coca Cola as a health conscious choice. On top of that, the labor was near free by western standards, the syrup price lock is so low, and the shipping is handled by the natives.

Coca-Cola has also been accused of massive civil liberties violations due to their opportunistic nature in South America.

This is usually too fringe for me to post, but http://killercoke.org/


It's not just Coke, though obviously they're an interesting case that's particularly close to home in e.g. Mexico. But many american companies have gotten contracts to privatize water resources and blatantly break the contracts, sometimes even providing people with worse water than what they were already getting.

However, I don't think any of that would have been possible without the american military, though to say that Coke is so successful because of military action is rather absurd. Yes, it's probably true, but Coke's actions are so far removed from the military action (that happened decades, if not a century, ago) that it's a little dramatic and silly.


> Is the US' international reach down to its military, or its money?

You can't ignore the interrelation of the two. One of the things that made the U.S. rich was our being a superpower allowed us to remodel the world in our image after World War II, making it a market for American goods, and one that operated on American terms. Another was the period of relative peace that we have had over the last 60 years, peace that has been the result of American military hegemony and peace that has allowed international trade and markets to flourish.

If the U.S. had not spent the last 50 years being the dominant military power, do you think it would still be the dominant economy? Money by itself doesn't protect you, it only helps you buy guns. Guns, in turn, let you back every market transaction with the implicit threat of force, and fend of other people who have guns who might find it more convenient to simply take things by force instead of engage in market transactions.


> Is the US' international reach down to its military, or its money?

I think it's down to the military, to be honest (Note: I'm completely biased by my own affiliation with the Navy).

However Coca-Cola may have got their start, they are now a multinational and can't be claimed to have any great allegiance to U.S. interests.

The military is what gives the U.S. the clout to work diplomacy and lead policy amongst the nations. I think the best example of this is the South China Sea which is looking increasingly resource-rich. China has expressed great interest in this region (right up to the borders of the Philippines, Vietnam, Malaysia, etc.), and is currently on a crash program to greatly expand the PLAN (People's Liberation Army Navy).

This is one of the driving reasons that President Obama and the DoD have enacted a "strategic shift" to the Pacific/Asia area because even in areas where the U.S. doesn't have a direct economic interest, the U.S. has indirect economic interests, in keeping natural resources within the effective economic control of their allies.

China has already heavily clamped down on rare earth production as a tool of economic and international political policy, so they've already demonstrated that they are willing to use monopolies on natural resources to their advantage (I'm not saying this to complain; just calling it how it is).

Money has substantial underpinnings in psychology (which is to say its value fluctuates wildly depending on what people think it's worth). And, sometimes you can't simply buy a country off. China is the example now, but for much of the period you discuss the example was the U.S.S.R. The Marshall Plan was successful in helping Europe recover, but the U.S.S.R. didn't allow its satellite nations to participate, and this isn't even going into the U.S. and Allied military efforts that kept the U.S.S.R. from expanding even farther.

When diplomacy fails the last resort for a nation's interests is the military, and the perception that its services are actually available.

I agree with rayiner on this much; Americans on average are very well off compared to much of the rest of the world. I would go further to say that Americans don't understand that their great advantage was never automatic. Not in the past; not in the future.

Now, given that the U.S. military was off doing what it was doing it would be foolish to claim that the follow-on economic effects weren't also important in U.S. hegemony, but I don't think economic factors played the major role.


Since the founding of the nation, the US Navy has played a different role than most imperial navies played. It rarely interferes in the trade between any other two nations, and has focused on international commerce being relatively safe and unfettered.

It's a more productive role, but it also means that American businesses have to be able to compete on their own merits, rather than being able to rely on exclusive access to markets.

Creating the conditions where businesses are free to thrive is a little different than being responsible for their success, though.


Why is it you do not care about the US consuming that much? Do you not care that 96% of the world only has 75% of the world's resources? Are you really so centered on yourself and your culture you literally want us to exploit the rest of humanity?

I don't think it's unfair, just morally despicable.


The US produces 22% of the world's GDP. There's nothing despicable about consuming what you are producing.

What is despicable is people who think they are entitled to the labor of others for free.


> There's nothing despicable about consuming what you are producing.

I agree, what's despicable is ignoring the rest of humanity. No, there's no entitlement (whatever that means really, a pejorative term for rights), but I do think you have a moral obligation to help people who need it.


I want China and India and Africa to have first-world standards of living, with similar per-capita GDPs. That will be awesome, both for them as well as for the US and Europe.


Yes, standards of living is the big thing, and not just across china, india, and africa. I would be fine with the US's dominance if I though other people in the world could have satisfying lives where they don't have to worry about employment (and the resulting food, shelter, health care). But, we are probably decades from achieving that in even China and India, both of which have a lot to offer the world even now.

Unfortunately, the US also has many inherent resource advantages (pretty amazing farming, for instance), which much of the rest of the world doesn't have. I really don't see at least the arid parts of Africa competing any time soon on material goods, and they don't have the education or cultural draw to attract production of intellectual goods. So at some point, the world does need to help itself out. It's not just going to magically fix itself without people helping each other.

I guess I should make this clear: I'm not advocating some kind of world socialism thing. I'm pretty sure things like classes are inherent in human societies. But I would like to drastically reduce the difference between the poorest and the richest people, and I do want to make sure that the basic things we take for granted in the US are available everywhere.


How much would you pay to save the life of your wife? Your best friend? An acquaintance? A random American? A random Somali?

The further away, in relation, a random human is from myself, the less that person's well-being affects me directly. It is, therefore, entirely rational to care less about their well-being than the well-being of humans closer to me.

The morality of that is neither here nor there--and indeed it strikes me as a very corrupt system of morality that rejects one of the most basic of human instincts.


Well, you're envisioning a world where your "moral" living, if you can get away with than Ayn Randian bullshit, is actively removing the ability of many other people to do the same. By pretty much every moral system, America is a pretty shitty place in a worldwide context. You think Kant, who wrote "Perpetual Peace", or John Stuart Mill, who advocated generating the most amount of happiness globally and said the best pleasures are intellectual (read: what people pirate on the internet), would approve of the way America (and Europe) holds the rest of the world hostage, economically and militarily? And honestly, most people on this site live far, far above what is necessary for a good life, in the sense of good health, food, and stability. It's a little sickening to see people not only ignore the rest of the world but to claim that it's "moral". Go spend a day watching people starve or die of curable sickness and then defend buying that nice car or that new computer. Hell, go into the ghetto and claim that what the upper class does to the lower classes (which is much nicer than what America does to the rest of the world) is moral.

Look, we all want to provide for our loved ones, but to claim that the level of excess we all indulge in is moral is just disgusting. I literally want to vomit at the thought and I'm ashamed to share a citizenship with you—at least I have the grace to admit that I'm a pretty shitty person for not giving back to the world to the extent that I could.

And at least I do SOMETHING (namely, volunteer and give unneeded money to efficient charities) to save the life of someone outside the US, which is more than most people do. I'm pretty sure the view of people suffering in third world countries is economically an entertainment product sold by CNN and christian charities.


How many rural villages in China were polluted from a nearby factory producing components of the computer you used to make this post?

Every single person posting in this thread is guilty of consuming far more resources than a majority of global inhabitants. The time and energy to even have this specific debate is mark of privilege. What's the solution? A global return to agrarian subsistence living?

I get where you are coming from, but I think the battle is already lost. The "haves" have always, intentionally or not, screwed over the "have-nots", and while it varies by degrees based on how little or much you "have", it ultimately comes down to the innate selfish nature of creatures living in a world of scarcity.


Hey, I already admitted I was as guilty as the rest of this country. But how the hell do you avoid products from china? Shit's impossible. I'd much rather make china (and india) rich enough to divorce themselves from the states, it would also help us reduce dependency on people who hate us (for a pretty good reason, I think).

As for a solution? I don't know, I really don't, and I suspect it won't be addressed until it absolutely needs to (overcrowding?). But I don't think that's a valid excuse to GIVE UP and continue to be a blatantly selfish nation. I think that if everyone gave a significant portion of their paycheck to efficient charities, the world would be a much better place. It doesn't even need to be charity, most people just need a little help to bootstrap themselves: http://www.kiva.org/start

> The "haves" have always, intentionally or not, screwed over the "have-nots", and while it varies by degrees based on how little or much you "have", it ultimately comes down to the innate selfish nature of creatures living in a world of scarcity.

I totally agree, I think this is a natural phenomenon in society (if the world natural means anything). However, we can raise the standard of living for everyone, so even the have nots aren't living in hell on earth, and reduce the distance between someone who is broke and someone worth many billion.


I don't know, I wouldn't necessarily want to be associated with this. An hypersonic plane, and CPGS technology in general, looks for the layman like me, more like a tool for a very limited type of extremely hard force projection. Well, maybe it could be used for reconnaissance, at most. But it's not particularly useful for counter-terrorism, since that takes on ground intelligence. It's useless for defense. It's not even a deterrent, you won't go MAD with it; the whole point of CPGS is that a strike with this thing should not guarantee a nuclear or ballistic response, after all.

To put it plainly, this plane is made for intimidation. If the USA is to support its standard of living on it, then it's not worth supporting.


Crazy, first thing I did was google how far it is to Tehran (albiet I'm Iranian). Seems like 30mins from New york at mach 20.


Despite the "conventional" label, how are countries this thing passes over going to know you didn't pop a surprise nuke on it?


They can't, if you launch the thing on top of something that looks like a nuclear ICBM and follows a ballistic flight path like a nuclear ICBM does. If that happens, the person on the other end is likely to jump to the conclusion that it is a nuclear ICBM, even if you insist it isn't. Which puts them on the spot to launch their own nukes, if they have any, before yours arrives. This "discrimination" problem has been a big one for the Prompt Global Strike program since its inception.

The vehicle in the story is part of the Air Force's attempt to solve this problem, by delivering the PGS payload via a spaceplane that flies in a flatter suborbital trajectory rather than an ICBM's higher trajectory. This is supposed to make it clear to the people on the other side that whatever has just been launched at them is not a nuke. It's unclear how successful this would be, though, since the spaceplane still has to be launched on a missile (possibly triggering any missile-launch early warning systems the opposition has), and nobody knows if in the heat of a crisis different angles of trajectory would be sufficient to reassure an anxious decisionmaker that they're not witnessing the beginning of a nuclear first strike.


Recent follow-up to the parent's old article: http://www.space.com/15388-darpa-hypersonic-glider-demise-ex...


More recent, but still 11 months old. It's pretty cool to look at the trajectory maps while remembering that the flight lasted 9 minutes Mach 20 (around 7000 m/s) is fast. :)


I found it really interesting to read about the underlying tech, scramjets: http://en.wikipedia.org/wiki/Scramjet


I don't think the HTV-2 uses (or used rather, since this was in 2011) a scramjet though, but uses a rocket engine. The HTV-3X was supposed to use a scramjet it seems, but that was cancelled.

http://en.wikipedia.org/wiki/DARPA_Falcon_Project


As I understand, you can't hit those speeds with just a rocket engine. The HTV-2 is considered a rocket glider - it needs a rocket to propel it to altitudes and speeds where the SCRAMJET can kick in (as the scramjet itself has no moving parts).


You can hit those speeds and beyond with a rocket engine. They don't really have a speed limit, they'll keep accelerating something (provided their force is greater than the drag and any other retarding forces) until you turn them off. Eg, a payload into earth orbit, which would be about Mach 25 if there was some atmosphere. Or significantly faster if you're putting a probe on an escape velocity, for example the Pluto probe New Horizons, which was launched with a solar escape velocity that would be equivalent to about Mach 50 (all sea level).

The advantage of the scramjet over a rocket is that you don't have to carry the oxidiser in a tank with you (like a conventional rocket). You get it from the atmosphere. But being inside an atmosphere making thermal management a big challenge, as the article describes.


I am almost positive I have video of this aircraft. I took night video (1/13/13) of an aircraft near the Everglades, the aircraft moves so fast it appears that I am moving, but I was stationary. When I get home I will upload the video and add a link here to see if people agree.


There as yet to be a third flight. DARPA is surprisingly open about the Falcon HTV-2 test flights. The releases have included more info that I would have expected.

DARPA was actually live tweeting the 2nd flight.


Here is the video: http://www.youtube.com/watch?v=f3VqiPhsnMM&feature=youtu...

As "open" as DARPA is they are subject to confidentiality and are only allowed to disclose what the DoD allows them to disclose. I am no conspiracy theorist but compare the shape/light of the aircraft in my video to the artist night time rendition from the OP article. Even if the aircraft in my video is different, I can tell you I have never seen anything anywhere near as fast as the aircraft in my video including F-15's, F-16's, F-18's or the space shuttle when it lands (which breaks the sound barrier at very low altitude).


Thanks for sharing the video. Yeah, while its not Falcon there are tons of classified launches coming from the Cape. Do you remember if the vehicle was flying south or east?


Sorry for the misunderstanding, the video is not from the Cape but the Eastern edge of the Everglades around South Miami. The aircraft was traveling North, seemingly along the edge Everglades.

There is a Air Force Base very near (10-15 miles)in Homestead, FL and a Navy Base in the Keys (over 100 miles), still it not unknown for the Navy to do exercises that far North, but I think a single aircraft at night might be unusual.


This article is from 2011, and there are no known tests since then.


until now


Source?


If the US is going to field these weapons, we need to be cool with Russia and China tossing around non-nuclear ICBMs- because that is what this is.


Why do we need to be cool with it? The best-case scenario for the U.S. is having these weapons, and using its de-facto subsidization of Europe's defense to get U.K., France, etc, to push, via the U.N., Russia and China not to have these weapons. Unlikely to succeed, because after all who the hell cares what the U.K. and France have to say, but that should be the end-goal.


You do know that Russia and China are both permanent security council members, so what you describe - bullying Russia and China into taking a position on this they do not want to take - is not possible?

Maybe this is cold war style thinking on my part but if I were China I would think to myself "yes, United States, please keep building that phenomenally expensive conventional weapon that would be really dangerous against the kind of surface fleet you have but we don't. That's a really... great... strategy you've got there." While publicly protesting against it, of course.


> non-nuclear ICBMs- because that is what this is.

Well, no, it's not. It's not a missile, it's not ballistic, and I don't know if the range is truly intercontinental. Not that the Russians and Chinese won't be concerned, but it is a rather different thing (and a much harder engineering problem).


You're right it's not a ballistic missile, but it's end goal is in many ways the same:

"Prompt Global Strike (PGS) is a United States military effort to develop a system that can deliver a precision conventional weapon strike anywhere in the world within one hour, in a similar manner to a nuclear ICBM"

http://en.wikipedia.org/wiki/Prompt_Global_Strike


It did the equivalent of Boston to North Carolina in 3 minutes. Crazy testing something that covers so much distance so fast.


I commented earlier that I thought I recorded this aircraft at night on (1/13/13), people already bashed me saying this aircraft has only flown 2 times blah, blah, blah... (ever hear of military testing? They don't tell the public)

Here is the video: http://www.youtube.com/watch?v=f3VqiPhsnMM&feature=youtu...

Why do I think it is same aircraft? When reading the OP article I immediately identified the artists night time rendering as the same aircraft I recorded in the video (video quality does not do it justice, but in person I can verify it looked identical to the artist rendering). Separately, the aircraft I recorded is by far the fastest thing I have ever seen, not in some UFO conspiracy way, but that I fly aircraft, attend airshows (F-14, F-15, F-16, F-18), saw Space Shuttles land (breaks sound barrier at low altitude) and I can saw I have never seen anything move as fast as the aircraft in my video.


  Darpa Maintains Control of Unmaned Aircraft at Mach 20 
...for three whole minutes!


Sounds like a lot to me. For the first DARPA Grand Challenge, for example, no car finished the race. The farthest went 7 miles.

http://en.wikipedia.org/wiki/DARPA_Grand_Challenge_(2004)

The next year 5 vehicles completed.

http://en.wikipedia.org/wiki/DARPA_Grand_Challenge_(2005)

Also, consider all of the rocket failures in the 1960's and we still made it to the moon by the end of the decade.


Don't forget, it traveled 650 miles in the process.


at Mach 20, in our atmosphere with all the things it can collide into, and the latency that it experiences between itself and the ground...

that's an incredible feat.


or 1200 km.


Pretty sure this is 'old tech' because of the successful test of the Advanced Hypersonic Weapon.

The Prompt Global Strike program seems to have moved on to other options.

http://en.wikipedia.org/wiki/Prompt_Global_Strike


Watching that video feels like something out of Kerbel Space Program: http://www.youtube.com/watch?v=DWBgUnL_ya4


mach 20 = 24 500.88 kmh (~6800m/s)

This is incredibly fast. Distance New York to Paris : 5851km[1] it would take 14 minutes for this plane to do the distance.

[1] http://www.wolframalpha.com/input/?i=paris+to+new+york


Why do we even reasonably need something this fast?

Wouldn't it be much more cost-effective to merely link up with strategic partners in other countries (Germany / Israel; Philippines; etc.) to give us the distribution we need for "conventional" missiles that would hit in the same timeframe?


Missiles can be shot down by state actors, non-state actors can hide deep in areas which are out of range of the U.S. or its allies. But launching anything on an ICBM makes it almost impossible for other nations to distinguish from a nuclear missile launch.

Of course, if Prompt Global Strike is capable of carrying cargo with it then maybe countries like Russia or China would suspect it can also carry a small nuclear warhead, so it may be that concern doesn't completely go away.


I don't think it's in any country's interest to do a nuclear attack with anything but a blow that would cripple response, a small nuclear warhead seems like an invitation to go from tolerated and accepted to hated.


Why does it not have a mane?


It did have one, but it ablated.


When is the next test?




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