SABRE rocket engine passes significant precooler milestone

Reaction Engines’ precooler heat exchanger passed all test objectives in the first phase of high-temperature testing designed to directly replicate supersonic flight conditions.

The precooler is a key element of Reaction Engines’ SABRE (Synergetic Air-Breathing Rocket Engine) hydrogen-fuelled engine, which uses atmospheric oxygen in its combustion cycle, switching to an onboard supply of liquid oxygen once out of the atmosphere. The precooler ensures that the engine core runs with cold inputs and keeps the core components cool despite the heating effect of its high velocity.

The ground-based tests saw the precooler quench the 420°C intake airflow in less than 1/20^th of a second. The intake temperature replicates thermal conditions corresponding to Mach 3.3 flight, which matches the speed record of the SR-71 Blackbird aircraft, the world’s fastest jet-engine powered aircraft.

Reaction Engines said the tests are the first phase in a test programme that will see the precooler test article (HTX) exposed to high-temperature airflow conditions in excess of the 1,000°C expected during Mach 5 hypersonic flight.