What happened
During the takeoff phase of flight, the left hook of the winch harness on the glider released unexpectedly from its center of gravity attachment. This uncommanded release caused the aircraft to yaw to the left, directing it toward a ditch located on the west side of the runway.
The pilot attempted to recover by applying right aileron and full right rudder; however, the aircraft continued into the ditch. The glider came to rest bridging the ditch while facing an eastbound heading. At the time of impact, the ditch was filled with broken and cut-down brush and saplings. During the collision, a broken branch penetrated the left side of the cockpit and struck the pilot's right calf. The pilot sustained one injury and remained hospitalized for five days following the accident.
The investigation
Prior to the accident, members of the glider club reported that both the left and right side cables had been properly hooked before takeoff. A subsequent inspection of the tow winch was conducted, but the examination failed to reveal any mechanical failure or malfunction.