The hybrid airliner was just one of the hot topics at the Experimental Aircraft Association's annual AirVenture air show, which wrapped up Sunday at Wittman Regional Airport in Oshkosh, Wis.
The plane would use traditional jet turbine engines for taking off and climbing, and switch to electric for cruising, the Chicago Tribune said Monday.
Boeing is working on a concept plane called the SUGAR Volt, using both electric and turbine engines, and it could be as large as a 737, while weighing far less and using two-thirds less energy, the paper reported.
On a smaller scale, designers are competing in the NASA-sponsored Green Flight Challenge. At stake is a $1.5 million prize for the first team to fly a personal aircraft that uses electricity or fuel cells. The winning design must average at least 100 mph, be able to cover a 200-mile distance, and achieve a passenger mpg equivalent of 200.