The idea that gliders don't need engines is not true. They just keep their engines in other airplanes. The folks at Honolulu Soaring use (among others), this 1979 Cessna Ector 305A (aka the L-19 "Bird Dog") to fill the bill, and it's a busy little airplane.
Pilots: "Big" Allen Sitt, Steve "Woody" Wood.
Cameraship pilot: Alan Miller
Pictures by Max Haynes