What is "motor glider"

n. A sailplane (glider) equipped with an auxiliary motor.

A motor glider is a fixed-wing aircraft that can be flown with or without engine power. The FAI Gliding Commission Sporting Code definition is: a fixed-wing aerodyne equipped with a means of propulsion (MoP), capable of sustained soaring flight without thrust from the means of propulsion. In the US, a powered glider may be certificated for up to two occupants, up to 850 kg maximum weight, and with a maximum ratio of weight to wing span squared of 3 kg/m. Similar requirements exist in European JAA/EASA regulations, at a maximum weight of 750 kg.