A piston aircraft engine that recaptures energy during deceleration and landing and uses it for supercharging during take-off and cruise, reducing fuel consumption and emissions, has been patented by US engine technology development company the Scuderi Group.
The air-hybrid engine uses Scuderi's split-cycle technology, in which the traditional four-stroke cycle is divided between two cylinders. Compressed air produced during normal operation is stored in a small tank and used to supercharge the engine to boost power for shorter take-offs, increased altitude and longer range compared with conventional piston-powered aircraft, the company says.
Scuderi's split-cycle engine has separate compression and power cylinders, which can be optimised for their respective functions (Flight International, 11-17 April). Gas is compressed in the first cylinder then transferred to the power cylinder for combustion. Both cylinders operate once per crankshaft revolution, while conventional engines require two revolutions per cycle.
West Springfield, Massachusetts-based Scuderi says the air-hybrid engine's light weight and internal supercharging make it ideal for unmanned air vehicles. The company also claims its design offers higher power and better fuel efficiency than electric hybrid engines, at lower cost. Scuderi plans to license its technology and expects prototype diesel and petrol engines for ground vehicles to be completed next year.
Source: Flight International
