arisvega writes "DARPA attempted to fly the fastest aircraft ever built; the Agency’s Falcon Hypersonic Technology Vehicle 2 (HTV-2) is designed to fly anywhere in the world in less than 60 minutes. This capability requires an aircraft that can fly at 13,000 mph (~21000kph), while experiencing temperatures in excess of 3500F (~2000C). Program manager Air Force Maj. Chris Schulz does not see it as a failure; “We know how to boost the aircraft to near space. We know how to insert the aircraft into atmospheric hypersonic flight. We do not yet know how to achieve the desired control during the aerodynamic phase of flight. It’s vexing; I’m confident there is a solution. We have to find it.”"
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