The US NASA folks over at the Dryden Flight Research Center at Edwards Air Force Base in California successfully tested their third, and last, X43 scramjet yesterday (see the story from NASA here).
The unpilotted research aircraft reached almost 7,000 mph (~11,000 kph) during its 10-second run before gliding back to earth and splashing down into the Pacific. But data received during the brief flight will go a long way towards moving the state-of-the-art forward. It is extremely difficult to reproduce, on the ground, the kind of speed needed to operate scramjets. Hence, this real world test is helpful to gain the information needed to determine how well this type of air-breathing engine performs.
