Britain’s Reaction Engines has proved its groundbreaking engine technology can handle the intense temperatures of hypersonic speed, marking a significant milestone in the development of hypersonic flight and for an aircraft that one day could take passengers from earth to orbit.
The Oxfordshire-based company, which is developing a new class of hybrid engine known as Sabre combining traditional jet and rocket technologies, said it had proven the viability of its precooling system in conditions equivalent to a speed of Mach 5.
At this speed, the air entering a jet engine would hit 1,000 degrees centigrade, enough to severely damage components. Reaction’s precooler takes the air down to minus 150 degrees centigrade in less than a 20th of a second.
The test, completed two weeks ago at Reaction’s test site in Colorado, marked a world first and paved the way for hypersonic flight, said chief executive Mark Thomas.
“It’s the first time anyone has taken cooling technology to these levels and really made credible the potential for a high-speed precooled jet engine,” he said. “It is unique.” Previous hypersonic aircraft had relied on rocket engine technology, Mr Thomas said.
Mach 5 is more than twice as fast as the cruising speed of Concorde and some 50 per cent faster than the world’s fastest jet-engine powered aircraft, the SR-71 Blackbird. At that speed, an aircraft could cross the Atlantic in two hours.
The Sabre engine was originally being designed as part of a space-plane concept known as Skylon. Sabre uses jet engine technology that effectively “breathes” air to make 20 per cent of the journey to orbit, before switching to rocket mode to complete the trip. The company has since focused on the propulsion system and the pre-cooling technology that it believes has much wider applications. Reaction is expected to start building and testing a demonstrator engine next year.
Mr Thomas plans to commercialise the cooling technology, which he said could be used to improve the speed and fuel efficiency of existing jet engines. The precooler would also find applications in the automotive and energy industries, he said. Reaction planned to begin generating its first commercial revenues next year, he added.
Mark Sully, head of technology for advanced systems and propulsion, Aerospace Technology Institute, said the successful cooling test was highly significant for the aerospace industry.
“Managing the way aircraft engines cope with the extreme temperatures generated during operation is one of the primary focus areas of manufacturers, and this is even more critical for engines that operate at very high speed,” he said. “Not only will this deliver a world-class capability for the air-breathing rocket engine but it could also enable future jet engine designs with even greater efficiency and reduced environmental impact.”
The UK government stressed the importance of Reaction’s technology to its own ambitions for tapping into the growing commercial space industry.
“The Sabre engine is one of the UK’s most exciting engineering projects which could change for ever how we launch satellites into orbit and travel across the world,” said science minister Chris Skidmore.
Reaction Engines was formed in 1989 by Alan Bond, Richard Varvill and the late John Scott-Scott, known as the “three rocketeers”, who quit their day jobs to pursue their dreams of space travel.
The three were able to overcome challenges that had long puzzled experts at Nasa and Rolls-Royce, hitting on the pre-cooling concept that has since been validated by the US Air Force Research Laboratory.
Mr Varvill, Reaction’s co-founder and chief technology officer, said the successful test was a “momentous landmark” in the development of the Sabre engine. Sabre had “the potential to revolutionise both access to space and high-speed flight by powering aircraft to five times the speed of sound . . .[It] takes us closer to realising our objective of developing the first air-breathing engine capable of accelerating from zero to Mach 5.”
Reaction Engines has raised a total of £100m in the past three years, from public and private investors, including Boeing, Rolls-Royce and BAE Systems.