Sikorsky Firefly: An Electric Helicopter!!!!! Shown at Oshkosh-2010
Shown at the Oshkosh fly-in aircraft show in 2010, Sikorsky created this electric helicopter conversion by a one-to-one replacement of gas drivetrain with electric drivetrain. The high power electric motor comes from US Hybrid. The helicopter has a 15 minute flying time. So it's more of a prototype demonstration vehicle than anything practical, but a step in the right direction.