Oxfordshire-based Reaction Engines Ltd (REL), which is developing a revolutionary hybrid aerospace engine, has announced £26.5 million of new funding from investors including Boeing and Rolls-Royce.

The company is working on a propulsion system called SABRE (Synergetic Air Breathing Rocket Engine) that is part jet engine, part rocket engine and has the potential to accelerate aircraft to speeds of 2,500mph.

A key element is a compact pre-cooler heat-exchanger designed to allow Sabre to use oxygen direct from the atmosphere for combustion, instead of carrying it in a tank.

REL (www.reactionengines.com) believes it will transform the space launch market in the next decade and eventually usher in hypersonic travel around the world.

The latest fund-raising takes the total capital raised in the past three years to around £100 million. The British Government has already put in £60 million, while BAE Systems injected £20 million in 2015 and has invested again in this latest round.

Mark Thomas, chief executive of Reaction Engines, said: “This is a significant milestone for Reaction Engines, and I am delighted to welcome our new strategic and financial shareholders.”

“In addition to providing our largest round of private investment, these new partners bring invaluable expertise in both hypersonics and engine technologies, with significant access to target markets.”

REL has recently achieved a number of milestones in the development of SABRE, and it is on track for the test of the engine core in 2020 at a new facility being constructing in Westcott, Buckinghamshire.

The fund-raising will also allow REL to accelerate its commercialisation plans, with proprietary technology opportunities in motor-sport, electric-vehicle thermal management, waste heat recuperation, small satellite cooling and aero-engines.