British company Reaction Engines has tested the viability of its precooler heat exchanger in Mach 5 speed conditions at its test facility at the Colorado Air and Space Port, US.

The test has proved the capability of the precooler technology to operate in airflow temperature conditions representing Mach 5.

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The ground-based test marks a key milestone in the company’s development of the SABRE air-breathing rocket engine that could power hypersonic combat jets, civil aircraft, and reusable space vehicles.

Reaction Engines is developing the SABRE engine in partnership with BAE Systems, Rolls-Royce and Boeing HorizonX.

The UK Space Agency and European Space Agency are funding the programme to design, manufacture and test SABRE demonstrator engines.

The precooler heat exchanger is a key component that prevents the engine from overheating at high flight speeds.

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The test has demonstrated a world first by cooling airflow at speeds far greater than the operational limit of any existing jet engine.

During the tests, Reaction Engines’ precooler is said to have handled temperatures greater than 1,000°C in less than one-twentieth of a second.

Reaction Engines chief executive Mark Thomas 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.”

Tests were carried out as part of the company’s HTX hot heat exchanger testing programme under a contract secured from the US Defense Advanced Research Projects Agency (DARPA).

BAE Systems Air industrial strategy manager Phil Varty said: “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.”

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