Researchers from the University of Cambridge have successfully tested the world’s first aircraft powered by both an electric motor and a gasoline engine. Paul Robertson of the Cambridge Department of Engineering says, until quite recently the batteries needed for a hybrid electric airplane were simply too heavy for the job. But newer batteries are substantially lighter, which has allowed research on hybrid powertrains for airplanes to take off, so to speak.
Using a lightweight single seat Czech airplane called the Song, Robertson and his team have replaced the plane’s normal conventional gasoline engine with a smaller four-cylinder gas engine and an electric motor. When full power is required for takeoff, both work together. But when cruising altitude is reached, the electric motor is shut down and the gas engine throttled back for maximum range. The hybrid electric plane is capable of flying much further than it could before it was modified, and much, much further than the few pure electric planes that have taken flight.
The new smaller engine can also be used to recharge the battery in flight so the electric motor can be used again to facilitate a takeoff later in the trip. Think of it as a flying Prius Plug-In. As researchers continue to improve battery performance and reduce weight, the application of hybrid electric power to airplanes will likely expand to include larger aircraft soon.