NASA X-43A

NASA X-43a

As the next step in scramjet technology, NASA produced the X-43a.

Launched from a B-52B in 2004, the X-43A scramjet engine reached a new world speed record for a jet-powered aircraft - Mach 9.6, around 11,000 kilometres per hour (6,835 mph).

The dream of a winged craft reaching further than sub-orbital flight had come a step closer to reality, but the craft was still not reusable, or reliable.

(Image: NASA)