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The Military Science Technology

Hypersonic Test Aircraft Peeled Apart After 3 Minutes of Sustained Mach 20 Speed 191

coondoggie writes "DARPA's experimental Hypersonic Technology Vehicle (HTV-2), lost significant portions of its outer skin and became uncontrollable after three minutes of sustained Mach 20 speed last August. That was the conclusion of an independent engineering review board investigating the cause of what DARPA calls a 'flight anomaly' in the second test flight of the HTV-2. Quoting the report: 'The resulting gaps created strong, impulsive shock waves around the vehicle as it traveled nearly 13,000 miles per hour, causing the vehicle to roll abruptly. Based on knowledge gained from the first flight in 2010 and incorporated into the second flight, the vehicle's aerodynamic stability allowed it to right itself successfully after several shockwave-induced rolls. Eventually, however, the severity of the continued disturbances finally exceeded the vehicle's ability to recover.'"
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Hypersonic Test Aircraft Peeled Apart After 3 Minutes of Sustained Mach 20 Speed

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  • 650 miles in 3 minutes? I'm SO there!

  • Expert opinion (Score:5, Interesting)

    by Anonymous Coward on Friday April 20, 2012 @06:07PM (#39751209)

    As a person who flies hypersonic aircraft for a living this is notable on several layers.

    1. They did a test and it went far past hypersonic (M5).

    2. They achieved M20, altitude adjusted

    3. All that happened after 3 minutes is the materials failed

    4. It lasted 3 minutes!

    To me this is a stupendous success.

    I am a hyper-critic of most of the hypersonic tests we all hear about.

    Spend more money on this.


    • Re: (Score:2, Interesting)

      by Anonymous Coward

      You fly hypersonic aircraft regularly? You either are: an space shuttle pilot, a military test pilot breaking his clearance, or making shit up. Who modded this up?

      • Re: (Score:3, Funny)

        by poity ( 465672 )

        You run Linux regularly? You either are: a central processing unit, a graphics processing unit operating outside of its designed architecture, or making shit up. Who thinks this stuff up?

    • by Hentes ( 2461350 )

      Spend more money on this.

      Because it's good for...what exactly? I fail to see the practicality of a plane that goes so fast it burns itself to pieces.

      • Re:Expert opinion (Score:4, Insightful)

        by Chris Mattern ( 191822 ) on Friday April 20, 2012 @07:00PM (#39751763)

        Because it can teach you how to build a plane that goes that fast and *doesn't* burn itself to pieces. This is the closest we've ever gotten to that.

      • Re:Expert opinion (Score:5, Insightful)

        by chebucto ( 992517 ) on Friday April 20, 2012 @07:14PM (#39751899) Homepage

        The fact that they corrected the problems found in the first test, and have a clear idea about why the second test failed, speaks very well to this program. I look forward to reading more about it.

      • Re:Expert opinion (Score:4, Interesting)

        by El_Oscuro ( 1022477 ) on Friday April 20, 2012 @08:00PM (#39752397) Homepage
        Mach 20 happens to be about orbital velocity. [] Assuming they can improve the materials somewhat, being able to do that in a plane instead of a rocket would be pretty useful.
        • by strack ( 1051390 )
          they dont even need to improve the materials. at mach 20, you could just leave the atmosphere in well under 3 minutes, and with the addition of a small rocket motor, make adjustments to achieve orbit.
    • Re:Expert opinion (Score:4, Interesting)

      by Grayhand ( 2610049 ) on Friday April 20, 2012 @06:47PM (#39751627)
      What I found interesting is something similar happened to Chuck Yeager when he was trying to hit Mach 1. The aircraft developed a strong vibration as he approached Mach 1. At the time Mach 1 was pushing the limits of what materials and technology could handle. The forces involved at Mach 20 are insane so I would also consider it a major success and it proves the technology. Now it's a matter of refining the construction and materials to avoid the failure issue but it looks very possible. I do have to question the commercial potential though. I'm not convinced that material fatigue won't be an ongoing issue with that kind of constant stress. Even with the space shuttles which didn't face a fraction of the stresses they had two blow up. Both accidents were avoidable but what accident isn't with prior knowledge. The engines are capable but it could be a very long time until the materials are reliable enough for extended commercial use.
      • Shit. At those speeds I'd almost be expecting supercavitiation with all the force being on the leading edge and the rest of the vehicle being pretty much in a vacuum. That would make air intact sort of difficult I suppose. I guess I might go read TFA to see if there's a graphic of the craft.
    • by geekoid ( 135745 )

      "I am a hyper-critic" all hot air, and noise?

    • Re: (Score:2, Interesting)

      by Anonymous Coward

      You fly hypersonic (mach 5+) aircraft for a living? Really?

    • As a person who flies hypersonic aircraft for a living... JJ

      I don't see your name here []. Who are you? What do you fly? Please tell me it's not a flightsim!

      • by Above ( 100351 )

        I would not be surprised to learn that there were a few hypersonic aircraft pilots flying planes we don't know about from locations we don't get to see. Aurora for instance has been around for years in semi-rumor form, for instance. That would make it entirely possible there were hypersonic pilots not not the list you reference.

        • by ceoyoyo ( 59147 )

          Sure, but entirely impossible that those pilots would post about it on Slashdot. Unless JJ wants a quick exit from the hypersonic plane flying game and a head start on the classified federal prison one.

    • by Anonymous Coward

      I fly unmanned hypersonic aircraft. I would call these rockets spacecraft except they don't go to space.

      I and nobody else flies "in" them. The temperatures are too high.

      Even SS1 had a peak velocity of altitude adjusted 240 knots at sea level.

      The goal here is a 1 hour to target RPV. Not a passenger aircraft and not Fedex to China. This is a military thing. Rediculous cost.

      BTW you can see my M5 "aircraft" on the web anytime you want. Search for 152mm rocket in the USA. The 229mm one goes faster and the 45

  • by demonbug ( 309515 ) on Friday April 20, 2012 @06:07PM (#39751211) Journal

    They only need to achieve 39 more minutes of flight time and they'll match the range of a 787!

  • ... get one's velocity going so fast one's skin gets ripped off...

    James Han and Leigh Whannell are probably working on the plot right now...
  • Mass driver tech can accelerate buckets at 5000m/sec^2. Buckets using this hypersonic tech, a 6 km mass driver in a very high place, say Tibet, and we could chuck stuff into orbit at 1/100th the current cost.

    Am I missing something, or should we start construction?

    • by rdebath ( 884132 )

      Air drag goes up as a fourth power of the speed.

  • by rts008 ( 812749 ) on Friday April 20, 2012 @06:19PM (#39751327) Journal

    IMHO, this was not a failure, just another step forward. We learned something useful, to be explored/applied next.

    Good job, folks! Keep moving forward....

  • Hopefully this kind of project continues in DARPA instead of shifting their focus to non-research projects now that the ex-director has gone to Google [].
  • If advanced planes work perfectly, we will never get a Bionic Man.

    • If advanced planes work perfectly, we will never get a Bionic Man.

      Don't worry, I'm old enough to find that funny.

    • Yes, and soon enough six million dollars will be mere pocket change! Our cybernetic programs are getting cheaper by the decade!

  • Unless they are able to sustain an localized electromagnetic field to dampen and thus disperse such large force vectors on the surface of the object traveling and such high rates of speed what's the point?
  • Unobtainium

  • by DerekLyons ( 302214 ) <> on Friday April 20, 2012 @07:02PM (#39751789) Homepage

    Here's the actual press release (which Network World just cut-and-pasted): []

  • There goes another monkey in the name of science! I hope the pilot managed to stay in one piece......
  • The only practical way to obtain hypersonic speeds is to go suborbital, and that really enters the realm of rockets as heat shields are very heavy.

    I think the developers of the SR-71 could have predicted these failures. The SR-71 _only_ went Mach 4 or so, at altitudes of greater than 60,000 feet or so. And at full speed the plane was so hot that pilots couldn't touch the canopy of the cockpit (I think the skin temps were at least a 1000 degrees pick your unit) and the plane lengthened by some cons

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