Skin-peeling speed doomed hypersonic glider, U.S. says
By Larry Shaughnessy
A test flight of an aircraft designed to whip around the world at Mach 20 failed when the high speeds peeled the skin off the unmanned plane, Pentagon researchers conclude in a long-awaited report.
For nine minutes in August, the Defense Advanced Research Projects Agency flew its Hypersonic Technology Vehicle at speeds reaching 20 times the speed of sound - fast enough to fly from New York to Los Angeles in less than 12 minutes. But then, something went wrong, and DARPA is finally explaining what happened.
"The most probable cause of the HTV-2 Flight 2 premature flight termination was unexpected aeroshell degradation," the research group explained in a new statement on the test flight.
Translation: The unmanned glider was streaking through the atmosphere when its outer skin started to rip off the airframe.
DARPA knew friction from the glider passing through the air so fast would cause it to heat up. It also expected "a gradual wearing away of the vehicle's skin as it reached stress tolerance limits," based on ground tests.
"However, larger-than-anticipated portions of the vehicle's skin peeled from the aerostructure," the statement said. "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."
When that "anomaly" occurred, a safety computer slowed the glider down and it splashed down in the Pacific Ocean, where it's now probably an artificial reef with a moon roof.
The goal of the project is to create an aircraft that can fly anywhere in the world in under an hour to strike a target. The test plane was launched by a Minotaur IV rocket from Vandenberg Air Force Base in California, then separated from the booster and re-entered the atmosphere over the Pacific.
At Mach 20, friction from the surrounding air subjects the vehicle to temperatures of more than 3,500 degrees Fahrenheit (1,925 C).
DARPA said a group of independent experts decided they couldn't have predicted the problem. "The data from second flight revealed that extrapolating from known flight regimes and relying solely on advanced thermal modeling and ground testing could not successfully predict the harsh realities of Mach 20 atmospheric flight," the agency said.
A 2010 test also ended with the craft plunging into the Pacific. In spite of the problems, DARPA said it did learn a lot from the August test.
"We successfully incorporated aerodynamic knowledge gained from the first flight into the second flight," Maj. Chris Schultz, the program manager, said. And future flights will incorporate what was learned in the second test, he said.
@natlsecuritycnn on Twitter
rxpharmacycoupons https://pharmacylo.com/ buy online prescription drugs
Way cool! Some extremely valid points! I appreciate you writing this article plus the rest of the site is also very good.
https://cse.google.vg/url?sa=t&url=https://ocrv.life
Greetings! Very useful advice in this particular post! It is the little changes that produce the most significant changes. Thanks for sharing!
https://images.google.cc/url?sa=i&source=web&rct=j&url=https://commercialvanrepairshop.com
https://map.google.com.sl/url?q=https://ocrv.world
May I simply just say what a relief to discover an individual who truly knows what they're discussing on the web. You certainly know how to bring a problem to light and make it important. More people need to look at this and understand this side of the story. It's surprising you aren't more popular because you most certainly possess the gift.
https://local.google.co.ug/url?q=j&rct=j&url=https://ocrvcenter.co
Greetings! Very useful advice within this post! It is the little changes that will make the biggest changes. Thanks for sharing!
http://ruth-moschner-fanclub.de/link.php?url=https://usedforkliftsforsaleorangecounty.com
You are so awesome! I do not believe I've read anything like this before. So nice to find somebody with a few unique thoughts on this topic. Seriously.. thank you for starting this up. This site is something that is needed on the internet, someone with a bit of originality!
http://www.americanstylefridgefreezer.co.uk/go.php?url=http://ocrv.rocks
When I initially left a comment I seem to have clicked on the -Notify me when new comments are added- checkbox and now whenever a comment is added I recieve four emails with the same comment. Is there a means you can remove me from that service? Appreciate it!
http://maps.google.com.fj/url?rct=j&sa=t&url=https://ocrvfleetservices.com
Spot on with this write-up, I seriously believe this amazing site needs a great deal more attention. I’ll probably be back again to see more, thanks for the information!
https://moskraeved.ru/redirect?url=https://mastermindofmen.com
After looking into a number of the blog articles on your blog, I honestly like your way of writing a blog. I bookmarked it to my bookmark website list and will be checking back soon. Take a look at my website too and let me know how you feel.
https://cse.google.ee/url?sa=t&source=web&rct=j&url=https://commercialvanrepairshop.com
Way cool! Some extremely valid points! I appreciate you writing this write-up and also the rest of the website is very good.
https://local.google.as/url?sa=i&url=https://realchrisburns.com
http://www.samsungcoloringsite.com/__media__/js/netsoltrademark.php?d=www.customcampervans.com
Good post. I am facing a few of these issues as well..
https://map.google.sc/url?sa=j&source=web&rct=j&url=https3A2F2Ffleetvehiclerepairshop.com&sa=D&sntz=1&usg=AFQjCNGaY_nlK9ozc51fqwjiVdMaYZL7rg
Hi, I do believe this is an excellent web site. I stumbledupon it 😉 I will come back once again since i have bookmarked it. Money and freedom is the best way to change, may you be rich and continue to guide other people.
http://support.persits.com/product_tip_redirect.asp?id=17&url=https://aikareborn.com
http://www.tawelectronics.com/popup.php?url=https://realchrisburns.com
Way cool! Some very valid points! I appreciate you writing this article and also the rest of the website is also really good.
https://www.local.google.sm/url?sa=t&source=web&rct=j&url=https://realchrisburns.com
I could not resist commenting. Exceptionally well written!
https://google.dk/url?q=j&sa=t&url=https://realchrisburns.com
Hi! I could have sworn I’ve been to this blog before but after looking at many of the articles I realized it’s new to me. Nonetheless, I’m definitely happy I came across it and I’ll be book-marking it and checking back frequently!
http://maps.google.com.bd/url?q=https://boxtruckrepairshop.com