Last year a test flight of the US Falcon Hypersonic Technology Vehicle 2 was carried out over the Pacific Ocean.
The Los Angeles Times reports that the vehicle took off from Vandenberg airbase onboard a Minotaur IV rocket. It was then released and dived earthwards and, once levelled off, it travelled hypersonically at a stable Mach 20 (twenty times the speed of sound) over the Pacific for three minutes.
The test was ended early though because of the massively high temperatures that were created as parts of the craft’s skin began to peel back at such high speeds.
The Lockheed Martin Corp Falcon is made from a carbon composite and designed to withstand the expected 3,500 degree heat.
“The initial shock wave 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. That’s a major validation that we’re advancing our understanding of aerodynamic control for hypersonic flight.” DARPA Acting Director Kaigham J. Gabriel said in a statement.”
So far there have now been two flights at a cost of $320 says the LA Times.