While in some people’s minds it might stretch the definition of a “hybrid,” Eurocopter’s electric/turboshaft AS350 helicopter a few days ago successfully completed a flight with an electric backup motor. In this case, the motor doesn’t power the main blades for normal flight but assists during autorotation, which, according to Eurocopter, took much of the uncertainty out of the process. An autorotation is the maneuver helicopter pilots use to land the helicopter after the main engine fails. In the case of the AS350, there is typically only one engine, though the technology demonstrator could rightfully be classified as a twin, or so we’d guess.
The supplemental motor is a compact electric unit powered by a lithium polymer battery. Eurocopter has not released specifications or details on the methods by which the secondary motor transmits its power to the drive system. The AS350 is one of the most successful helicopters in the world, with more than 4,000 flying. And Eurocopter seems serious about applying this technology to its products, which could conceivably bring some degree of twin engine safety to single engine helicopter operations.