Beta Technologies and GE Aerospace have used a hybrid-electric propulsion system to help power an aircraft’s takeoff for the first time, in what they say is a world first for a commercial-type aircraft.
During the test, at Beta’s flight-test facility in Plattsburgh, New York, a modified Saab 340B took off with a conventional GE Aerospace CT7 gas turbine on one side and a hybrid-electric engine on the other, the electric motors and battery adding power to deliver the thrust needed. Previous flight tests by the two companies had used the hybrid-electric system only during climb, cruise and descent – not the more demanding takeoff phase.
The hybrid engine is a fully integrated megawatt-class, multi-kilovolt system, and early observations showed the hybrid-electric takeoff was quieter than using the gas engines alone. The 1MW system sits in the aircraft’s right nacelle, with the original CT7 on the left.
Arjan Hegeman, GE Aerospace’s vice president of future of flight engineering, said, “GE Aerospace is advancing the building blocks that will define the future of hybrid electric flight, now successfully demonstrating a more efficient commercial takeoff with a hybrid electric system. Step by step, we’re proving out a suite of next-generation technologies, from hybrid systems to Open Fan architecture.”
The work is part of NASA’s US$260 million Electrified Powertrain Flight Demonstration (EPFD) program, launched in 2021, with Boeing’s Aurora subsidiary also a partner. The same aircraft made the world’s first hybrid-electric flight above 30,000ft in May and the first hybrid-electric crossing of the Atlantic to reach this year’s Farnborough Air Show.
The Saab 340B’s hybrid system combines GE Aerospace motor-generators, power converters and inverters, Avio Aero gearboxes, Dowty propellers and Unison heat exchangers with BAE Systems batteries, in a nacelle supplied by Aurora. Flying above the Saab’s normal 25,000ft ceiling was only possible in hybrid-electric mode.
Both hybrid-electric and Open Fan technologies are being developed through the CFM RISE (Revolutionary Innovation for Sustainable Engines) program, a demonstrator run by GE Aerospace and Safran’s CFM International joint venture that targets more than 20% better fuel burn than today’s engines. Open Fan removes an engine’s outer casing to allow a larger, more efficient fan.
