Hypersonic speeds are speeds more than 5 times the speed of sound. The physics of airflow is very different at these speeds and the air friction causes severe heating of air. Reaction Engines, a partner of BAE Systems of UK is developing the SABRE, an air breathing rocket engine. This engine is capable of pushing aircraft to hypersonic speeds above Mach 5. One of the major components for the engine is a pre-cooling system. The is pre-cooling system has several applications in aviation, space and road transportation also. It is an enabling technology for several futuristic propulsion systems.

Reactions Engines has conducted the second series of tests on the cooling system at its testing facility in Colorado, USA. During the test, the company’s coolers could quench air flow at 1000 deg C in less than 1/20th of a second. These are parameters similar to a Mach 5 speed flight. The tests demonstrated the capability of the system to successfully cool air flows at speeds way beyond the normal operating parameters of existing jet engines. In an earlier test conducted in April 2019, the coolers had been able to succesfully quench air flows at temperatures exceeding 420 deg C, matching the parameters of a Mach 3.3 flight.

Courtesy BAE Systems

On the occassion Mark Thomas, Chief Executive, Reaction Engines, said, “This is a major moment in the development of a breakthrough aerospace technology which has seen Reaction Engines’ precooler tested at Mach 5 airflow temperature conditions, smashing through previous achievements at Mach 3.3 temperatures and paving the way for hypersonic flight. In addition to its use in our SABRE class of air breathing rocket engines, there are numerous exciting commercial applications for our precooler technology, which delivers world-leading heat transfer capabilities at low weight and compact size, and we are seeing significant interest from a range of potential customers and technology partners.”

Reactions engines has partnered with BAE as well as raised nearly GBP 100 Million from various sources. Phil Varty, Industrial Strategy Manager for BAE Systems Air, said about the cooperation between Reaction Engines and BAE Systems: “Working together with Reaction Engines, we’re pushing technological boundaries to develop the SABRE air breathing rocket engine, an engine which could revolutionise hypersonic flight and space access. The precooler heat exchanger is an enabling technology that we also have a real interest in for a number of other defence and commercial applications, including future combat aircraft and maritime vessels.  These latest trials demonstrate what can be achieved when we bring together the boldest and brightest minds from across the UK industry together. Our engineers have brought expertise in simulation, modelling and test & evaluation to the programme and we continue to work closely with Reaction Engines through the placement of graduates across both companies, exploiting the very best in small company thinking and large company experience.”

The SABRE engine is being developed as a part of a space access system being jointly developed by the UK Space Agency and the European Space Agency.