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Reaction Engines chases the elusive prospect of a hypersonic fighter jet
LONDON — A hypersonic propulsion company backed by Rolls-Royce, Boeing and BAE Systems has taken a step closer to developing an engine capable of powering combat jets and other aircraft at speeds of up to Mach 5 following tests of two subsystems vital to the success of the design.
British-based Reaction Engines said the recently completed tests of full-scale heat exchanger and hydrogen pre-burner subsystems validated the design of what are key components required to supply heat energy and air to the core of the air-breathing engine.
Reaction Engines, which also has a U.S. test operation in Denver, Colorado, has worked for decades on its Sabre synergetic, air-breathing rocket engine for aerospace applications, including for combat jets and to assist vehicles into space.
In recent years the work has attracted BAE Systems, Rolls-Royce, Boeing Horizon X and others to invest in the company. The British government has also ploughed millions of pounds into the company’s design effort. Ministry of Defence funding has gone toward Reaction Engines’ work with Rolls-Royce and BAE for the possible application of high-Mach know-how on the sixth-generation Tempest fighter project.
The latest test success comes as the field of hypersonic technology becomes increasing attractive in the West, triggered in part by rapid technological advances by potential adversaries.
Other Western engine companies are also investing in hypersonic propulsion. Pratt & Whitney recently confirmed it is developing a hypersonic engine it calls the Metacomet. The company designed the J58 engine that powered the SR-71 Blackbird spy plane to a record speed of about Mach 3.4 in the 1960s.
Adam Dissel, the president of Reaction Engines’ U.S. operation, said the effort to advance in the hypersonics sector is generating plenty of cross-Atlantic dialogue between Washington and London.
“There is great collaboration between the U.S. and U.K., and there are lots of discussions happening as to how we collaborate on these technologies,” he said.
The success of the trials on the heat exchanger, known as the HX3, and the pre-burner is another step in the right direction to maturing Reaction Engines’ technology. The latest tests follow trials undertaken in 2019 in Denver, where the company undertook high-temperature airflow testing for the Defense Advanced Research Projects Agency’s HTX program.
The company reported at the time that its proprietary ultra-lightweight heat exchanger used in the test was exposed to hypersonic conditions approaching 1,000 degrees Celsius, or roughly 1,800 degrees Fahrenheit. The heat exchanger performed its pre-cooler function by quenching about 1,800-degree Fahrenheit temperatures in less than one-twentieth of a second, according to the company.
Dissel said that together the three tests successfully demonstrate key subsystems not previously used in an aerospace environment.
“The company is very focused on maturing the subsystems that are fundamentally new to aerospace. Pre-cooler was the big one, and now with the innovative HX3 heat exchanger and pre-burner tests, these are three key components very specific to Sabre,” he told Defense News on March 5. “We are well past the hump in terms of validating the fundamental pieces. Putting it together as an integrated device able to go five times the speed of sound is still a big challenge, so from an overall integration standpoint we are at the beginning.
https://www.defensenews.com/global/...elusive-prospect-of-a-hypersonic-fighter-jet/