Major airframers and component suppliers have instituted new research programs and initiatives to develop electric propulsion for light aircraft. The consensus among the participating parties is that battery and motor technology offering similar performance and endurance of small piston engines is roughly 10 years away. Spearheading these innovations at Oshkosh’s AirVenture this year is Sikorsky’s electric S-300C helicopter and Yuneec’s e430 electric light sport aircraft.

The S-300C, built by Sikorsky and partner companies, is expected to fly by year-end. Its 200-hp Lycoming piston engine and fuel tanks have been replaced by an electric motor from US Hybrid, and 45 amp-hour lithium ion battery packs from Gaia Power Technologies. This demonstrator aircraft is expected to have an initial endurance of 15 minutes, limiting flights to the traffic pattern.

Yuneec’s two-seat fixed-wing e430 offers new lithium polymer batteries boosting flight time to two hours, and an increased battery life of 1,500 recharge cycles. The company believes battery technology allowing a four-hour endurance is five to seven years away.