Accident Overview
A student pilot, who was also the builder of the glider, was conducting tows from a paved runway. After five successful tow releases and landings, the pilot attempted the first tow from a grass surface. The tow vehicle moved the glider to the starting point, the pilot boarded, and a second individual assisted in installing the canopy. The pilot checked canopy security with a push-up motion before the tow commenced.
Canopy Loss and Stall
At liftoff, approximately 38 knots, the glider struck a clump of grass. The canopy then separated from the airframe. The pilot raised his left arm to shield his face and believed he inadvertently pulled back on the control stick while avoiding the canopy. The glider stalled at an estimated height of 10 feet and subsequently contacted the ground.
Prior Canopy Latching Issues
The pilot reported having difficulty latching the canopy during previous tows and expressed the opinion that the latching mechanism might have been twisted.