Reaction Engines

Reaction Engines Limited (‘Reaction Engines’) is a privately held company based in Culham, Oxfordshire, UK. It employs over 200 staff across its sites in the UK and US. Reaction Engines develops the technologies needed for an advanced combined cycle air-breathing rocket engine class called SABRE (Synergetic Air-Breathing Rocket Engine), a leading contender for the next generation of hypersonic flight and space access vehicles.

SABRE is an innovative new class of aerospace propulsion that has the potential to provide efficient air-breathing thrust from standstill on the runway to speeds above five times the speed of sound in the atmosphere. The SABRE engine can then transition to a rocket mode of operation, allowing spaceflight at up to orbital velocity, equivalent to twenty-five times the speed of sound. Through its ability to ‘breathe’ air from the atmosphere, SABRE offers a significant reduction in propellant consumption and weight compared to conventional rocket engines which carry their own oxygen.

Central to the SABRE design is the ultra-lightweight heat exchangers (precooler) Reaction Engines has developed, which stop engine components overheating at high flight speeds. These are capable of cooling airstreams from over 1,000°Cto ambient temperature in less than 1/20th of a second with world leading compactness and low weight.

Reaction Engines’ proprietary heat exchanger technology has a wide range of potential commercial applications and the ability to revolutionise the approach to thermal management across a range of industries; from aerospace to motorsport, industrial processes, and the oil and gas industry.

Individual components of the SABRE engine have been successfully validated in an extensive research and development programme, successfully passing the Preliminary Design Review for a ground-based demonstrator.

In April 2019 Reaction Engines’ precooler heat exchanger successfully achieved all test objectives in the first phase of high-temperature testing designed to directly replicate supersonic flight conditions and futuretests are planned at even higher temperatures.

The ground-based tests saw Reaction Engines’ unique precooler successfully quench the 420°C (~788°F) intake airflow in less than 1/20th of a second. The intake temperature replicates thermal conditions corresponding to Mach 3.3 flight, or over three times the speed of sound.

Reaction Engines is currently constructing an engine test facility at Westcott, Buckinghamshire, where it will undertake a ground-based demonstration of a SABRE engine air-breathing core, together with the testing of critical subsystems.

Reaction Engines has raised over £100m in the last three years from public and private sources, which has supported its transition from a successful research phase into development and testing of the engine. In 2013, the UK Government announced a £60m commitment to aid preparations for the design, manufacture and testing of SABRE demonstrator engines. In 2015, the Company announced that BAE Systems had made a strategic investment in the company and committed to a working collaboration to accelerate the development of the engine. In April 2018, £26.5m was raised from investors including Rolls Royce and Boeing’s venture capital arm, HorizonX.