The glider was undergoing a test flight following an annual inspection. After being released the aircraft was climbed to 4300 feet prior to the commencement of a high speed descent. At an indicated airspeed of 110 knots the pilot reported that there was a slight buffet from the tailplane area. The descent was continued and at an indicated airspeed between 118 and 122 knots severe vibrations from the tailplane area were encountered. The airspeed was reduced and after completing a control check the aircraft was landed. Subsequent inspection revealed damage to the rear fuselage near the fin root. This accident was investigated by the Gliding Federation of Australia and was not the subject of an on-site investigation by the Bureau. The Federation's investigation indicated that the amount of freeplay in the horizontal tailplane of the aircraft was just within the limits specified in the manufacturer's manual the pilot was inexperienced for the task he may have actually reached VNE and his reaction to the vibration may have overstressed the aircraft.
