Description
At AERO Friedrichshafen I got a close look at a Stemme S10 that Klaus Ohlmann is rebuilding as an electric-hybrid aircraft.
It's a series hybrid: a 70 kW electric motor handles takeoff and climb on battery power, while a small 25 hp combustion engine works purely as a generator, recharging the battery in flight. That decouples range from battery capacity – long distances become possible as long as there's fuel for the generator. On top of that, the propeller can recover energy in flight, feeding up to 10 kW back into the battery.
Klaus Ohlmann wants to use this aircraft to fly around the world. The bigger idea: aging combustion engines in existing gliders could be replaced by this newer, safer hybrid setup.