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.
