Accident during winch launch, Discus b, gliderfield Lemelerveld, 12 April 2019
The pilot of the single-seat glider was ready for a winch launch from the westerly take-off point on the West-East strip. It was just after 14.00 hours. It was his second flight of the year. On the same day, he had conducted a training flight with the instructor on duty in a two-seat glider. This flight had gone well. The instructor notified the pilot that he was reapproved for solo flights.
There was a northeasterly wind of about 10 knots. After the pilot performed the cockpit check and the winch cable had been attached to the glider, he notified the
wing runner that he was ready for take-off. The pilot stated that his right hand was on the stick and his left hand on the release. After the light signal was activated from the start position, the winch operator applied power and the glider started moving. The wing runner, after having accompanied the glider for several metres, let go of the left tip. The wing runner stated that the glider’s right wing dropped after about 5 to 10 metres and started dragging on the grass. Another witness stated that the right wing tip fell to the grass almost immediately after the wing runner let go of the left wing tip. The tip remained in contact with the grass until the moment the glider started to rotate. The left wing came up, the glider rotated and left the ground. A witness stated that the cable remained attached to the glider and the glider rotated right by nearly 90 degrees. When the glider’s right wing was still on the ground and the glider was upright, the cable detached. The glider then cartwheeled to the right and hit the ground upside down, with the wings in horizontal position, on the other side of the winch path, under an angle of ca. 20 degrees and then came to a full stop. The longitudinal axis of the glider was parallel to the winch patch with the nose turned towards the winch.
The pilot suffered minor injuries. The glider was damaged; the canopy was shattered. The pilot had a valid LAPL(S) (Light Aircraft Pilot Licence Sailplane) and a valid medical certificate. He had a total glider flight experience of 1,182 hours (2,475 starts), 125 hours (75 starts) of which in the glider model in question. In 2018, he had done 17 flights with a total duration of approximately 11 hours.
The instructor on duty stated that there was an approximately 20 degree angle crosswind during the launch, and that the glider was positioned parallel to the winch track. The grass was circa 10 centimetres high. The pilot remembers little of the accident. He does not know whether or not he released the winch cable. The winch operator stated that he immediately dropped all power to the winch when he saw the left wing come up and the glider cartwheel over the right wing. The light signal from the take-off point was also turned off at the same time. A wing may drop due to a yaw motion in the early stage of a winch launch. It is important to keep a hand near the release at the start of a winch launch. If a wing threatens to touch the ground while the glider is rolling, the winch cable must be released immediately before the wing hits the ground.
This accident was publisjed in the Quarterly Aviation Report over the 2nd quarter of 2019.
