PROPULSION / ELECTRIC WHERE DO WE GO FROM HERE? BATTERY Our editors explore the future of general aviation propulsion technologies M any scoff at the notion of electrically powered aircraft. After all, what do you do when the batteries run out? Short-sighted, I say. Already, battery-powered, light two-place airplanes have the potential to fly for three hours or more, which would satisfy the aviation fix for many pilots. Such airplanes aren’t quite ready for prime time, but soon they will be. More practical applications for electric propulsion may include a hybrid approach that uses on-board generators to drive electric motors that drive propellers. Such generators might even be internal-combustion engines or perhaps fuel cells in the future. Regardless, most futurists believe we are entering an all-electric age, where internal-combustion engines will be phased out in favor of more efficient and simpler electric motors. Aviation is unlikely to be an exception to that movement over the long term. We explore the short- and long-term possibilities in this third and final part of our series on the future of propulsion. Share your feedback via comments on our Reporting Points blog and our Facebook page. —TO M H A I N E S , E D I T O R I N C H I E F 62 | AOPA PILOT September 2013