Australian scientists look to a future where hypersonic air travel is common and flight from Sydney to London takes two hours. Scientists from the University of Queensland recently launched a second rocket carrying a scramjet: an air-breathing supersonic combustion ramjet engine.

The rocket took the scramjet to an altitude of 314km about 1:45pm (CDT) above Woomera, in the South Australian outback and the scramjet kicked into action during a tiny six-second window shortly before impact.

This is the home of the program, where a hypersonic wind tunnel has allowed the concept to be delivered.

My best mate David Moore has come up with a good analogy for a scramjet: a two-stroke motor. A two stroke has no cams or valves; the movement of the piston alternately covers and uncovers the inlet and exhaust ports. When a two-stroke engine is operating at high revs, it is generating an alternate set of standing pressure waves. The pressure waves explain why expansion chambers improve performance and why the size of the ports and their precise location determine the performance characteristics of the engine.

Dave therefore describes a scramjet as two-stroke motor without pistons, because air entering the engine at a mach five minimum generates shockwaves, and the shockwaves serve as the compressor, combustion chamber and reaction chamber. It’s such a beautiful concept; the ultimate jet engine, no moving parts and fuelled by hydrogen.

This video shows a description of the flight.

This mission, Hyshot III, follows the historic Hyshot II launch at Woomera in 2002 and this video shows the assembly of the rocket for the first test.

During that flight, the team made history by becoming the first to achieve combustion in a scramjet engine in flight, following the failure of Hyshot I in 2001.

Professor Paull said scramjet-powered passenger jets were a long way off, but it might be possible to have a scramjet-powered vehicle within the next 10 years. The HyShot team aims to develop a scramjet plane capable of 7 to 10 minutes of free flight over 1000 kilometres, within 5 to 8 years.

There is a NASA concept for a hypersonic aircraft.