A British company called Reaction Engines Ltd.(REL) has accomplished what it calls “the biggest breakthrough in aerospace propulsion technology since the invention of the jet engine.” REL is in the process of developing an engine called SABRE (Synergetic Air-Breathing Rocket Engine), which the company claims will be capable of flight from zero speed on the runway up to Mach 5.5 enabling single stage flight into space orbit or trips from one side of the globe to the other in a little more than four hours.
The new engine uses a blend of jet and rocket technology. After more than 100 test runs, REL has shown that its pre-cooler is capable of cooling air from 1,000 degrees to 150 degrees C in 1/100th of a second without frost development.
An independent evaluation of the pre-cooler technology was conducted by the European Space Agency (ESA). “One of the major obstacles to developing air-breathing engines for launch vehicles is the development of lightweight high-performance heat exchangers. With this now successfully demonstrated by Reaction Engines Ltd, there are currently no technical reasons why the SABRE engine [program] cannot move forward into the next stage of development,” said ESA’s head of propulsion engineering, Mark Ford.
In addition to the pre-cooler, technologies proven by the early test runs include contra-rotating turbines, combustion chambers, rocket nozzles and air intakes.
With the function of crucial components now validated, the next stage for Reaction Engines is to build a complete engine demonstrator. The company expects the engine to fly in about three years with entry into service within the decade. While SABRE is designed for space access, REL is also developing a derivative engine called Scimitar, which the company claims will be capable of sustained Mach 5 cruise.