Club Libelle stalls and rolls inverted in winch climb transition

An experienced pilot was fatally injured when a Club Libelle 205 stalled on its third winch launch on type and rolled inverted onto the runway; airframe destroyed. The pilot — ~700 h total but only 3 winch launches in the last 90 days, recently cautioned by an instructor about pitching up too soon — launched from RWY 21. The glider climbed shallowly; despite low airspeed he pitched up as for a normal winch climb, stalled at ~50 m AGL and rolled over the left wing into the runway nose-first. No technical faults; winch delivered required line speed; mass/CG in limits; wind direction and density not optimal for winching.

1. Winch launch from RWY 21: Third winch launch on the Club Libelle 205 from grass RWY 21, in variable wind to 5 kt. Six earlier launches that day had been uneventful.
2. Low recent winch currency: The pilot had only 3 winch launches in the last 90 days and had flown the Club Libelle almost entirely within that period; an instructor had cautioned him about low speed.
3. Marginal winch conditions: Variable wind to 5 kt (with up to 5 kt tailwind component) and warm summer air — wind direction and air density were not optimal for winching per the investigation.
4. Over-rotation at insufficient airspeed: After lift-off the glider climbed away shallowly. Despite obviously insufficient speed, the pilot pitched the nose up as for a normal winch climb, transitioning to a steep climb attitude.
5. Stall and roll-off left: At ~50 m AGL the airflow stalled during the transition to climb, the attitude became unstable and the glider rolled over the left wing.
6. Inverted impact — fatal: The glider struck the hard-surface runway nose-first inverted; airframe destroyed; pilot fatally injured.