New Scientist Tech - Breaking News - Second scramjet tested over Australian outback: "Scientists in Australia launched an experimental hypersonic scramjet engine for the second time in a week on Thursday, as they work towards building a plane that could revolutionise air travel.

The scramjet, Hyshot IV, was launched aboard a larger Terrier-Orion rocket and reached an altitude of 325 kilometres before falling back to Earth. During its descent, the scramjet engine should have activated and propelled the craft to more than 8000 kilometres per hour (Mach 8)."