Scramjets

As the world enters the second century of powered flight, the X-43A, a new experimental aircraft developed by NASA -- powered by a revolutionary "scramjet" (supersonic-combustion ramjet) engine that uses oxygen from the air instead of on-board liquid oxygen fuel -- screamed into history at Mach 7. That's 5,000 miles an hour, or about 83 miles per second. Never mind supersonic. The age of hypersonic jet travel is dawning.

 Posted by glenn