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Hypersonic Test Aircraft Peeled Apart After 3 Minutes of Sustained Mach 20 Speed
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.'"
The technology exhibited here is completely independent of the fuel source on which it runs. Your comment misses the point.
And scientifically, it went around 750 miles in 3 minutes. In an atmosphere. That's a pretty damn awesome piece of engineering.
"Little does he know, but there is no 'I' in 'Idiot'!"
Yes. Science and engineering are often advanced by never doing anything you are not absolutely certain will work perfectly.
Why yes, I AM a rocket scientist!
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....
Down With Slashdot BETA!!! I've been around the corner and seen the oliphant; you can only abuse me from your perspecti
But Mach 20? Really? Does it really serve a purpose other than finding out that we can push the limits of things?
Purpose? Probably to build a long-range bomber that can hit a target anywhere on Earth a few minutes after it's been identified. Or to build a vehicle that can reach low Earth orbit and return. Or maybe just to see what's humanly possible.
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.
The English word fart is one of the oldest words in the English vocabulary.
This close to the bleeding edge, definitely. We have better models and more teraflops to run them than ever before, but real breakthroughs come from unexpected, unintuitive results. Remember how hard it was for most engineers to believe that mere foam could bash in a shuttle wing - until they fired an actual piece of foam at an actual leading-edge panel?
Flying real hardware is still the only way to conclusively
1. Learn Something (if it has problems) or
2. Silence the critics (if it works fine).
IMHO, while a good number of aerospace contracts can be criticized for either being pork or thinly veiled airliner-maker subsidies, that should be focused on those never producing an instrumented flight.