LS 4a steep winch climb, oscillations, roll-off at 50-70 m AGL

An LS 4a was destroyed and the pilot fatally injured on a winch launch from RWY 18 at Sultmer Berg near Northeim (Germany). Witnesses saw an unusually steep climb attitude immediately after liftoff and yaw oscillations about the vertical axis. At about 50 to 70 m AGL the glider rolled off over the left wing and impacted east of the runway. The right wing broke about two metres from the tip. Investigators found the trim set tail-heavy and the right airbrake extended, with no defects in the flight controls.

1. Winch launch from RWY 18: At about 16:00 LT the LS 4a launches from RWY 18 at Sultmer Berg glider airfield (Northeim) on a winch tow.
2. Steep climb attitude after liftoff: Immediately after liftoff, witnesses see the glider in an unusually steep climb attitude on the winch cable.
3. Yaw oscillations during climb: While in the steep climb, the glider begins to oscillate about its vertical axis.
4. Roll-off over left wing at 50-70 m: At approximately 50 to 70 m above the ground the glider rolls off over the left wing — the classic low-energy departure from a steep winch climb.
5. Impact east of runway centerline: The glider impacts the ground about 40 m east of the RWY 18 centerline and about 340 m from the threshold of RWY 36, lying transverse to the launch direction. The aircraft is destroyed and the pilot is fatally injured.
6. Trim tail-heavy; right brake extended: At the wreckage the trim is found in the tail-heavy position and the right airbrake is found extended. The right wing is broken about two metres from the tip with the tip section embedded in the ground. The elevator pushrod and tail boom are broken at impact; remaining control linkages are intact. No defects in the flight controls are found.