What happened
On 27 March 2005, a Janus C glider, registration ZS-GMR, was participating in a private flight operation at Estcourt Airfield. During the initial phase of a winch launch on Runway 01, the aircraft failed to accelerate to the necessary velocity. As the glider attempted to climb, the launch cable experienced a back release.
At an altitude of roughly 100 feet above ground level, the glider entered a stall. During the descent, the left wing struck the top of a small tree. The aircraft subsequently struck the ground in a flat attitude approximately 200 meters from the launch point. There were two people on board the aircraft during the incident, and both sustained injuries, though no fatalities were reported.
The investigation
Investigators examined the circumstances of the launch and the mechanical state of the aircraft. The winch operator noted that the launch occurred into a light headwind and observed that the glider appeared to have over-run the cable, leading to the premature release.
Regarding the aircraft's maintenance status, the Janus C was documented as airworthy, having been issued a Private Authority to Fly on 06 August 2004. At the time of the accident, the aircraft had flown 50 hours since its last annual inspection. The investigation confirmed that the person responsible for the inspection was properly accredited.
Findings
- The primary factor in the accident was the premature release of the launch cable.
- Because the aircraft had not achieved sufficient airspeed prior to the cable release, it entered a stall.
- The specific reason why the cable back-released unexpectedly could not be established by the investigation.