Australian scientists plan a second attempt on Tuesday to test a hypersonic “scramjet” engine they believe will one day allow airliners to fly at more than eight times the speed of sound.

The first test flight of the air-breathing engine failed last year when a booster rocket carrying the scramjet spiralled out of control.

Scramjets — supersonic combustion ramjets — could revolutionize air travel and satellite launches.

Expected to reach speeds in excess of Mach 8, or eight times the speed of sound, they could cut flying times between Sydney and London to just two hours from a current 24 hours in a sub-sonic jumbo jet. More here.