LS6 hits treetops with airbrakes likely deployed throughout flight

An LS6 18w struck treetops on a clearing approach ~14 km NW of Fayence; the pilot was uninjured and the aircraft substantially damaged. The pilot, aiming for a 750 km flight, released from aerotow at ~1,930 m near Mt Lachens. Descent rates of -6.8, -7, then -9.3 m/s matched the glider with airbrakes and gear out (L/D ~7 vs 48). The pilot blamed the air, did not check the brakes, and continued past La Chapelle until running out of height. Inspection found a 15 cm branch in the right airbrake slot and the handle in 'closed unlocked' — on the LS6 an unlocked handle self-deploys the brakes. Investigators cited the undetected airbrake deployment.

1. Aerotow toward Mt Lachens west face: The pilot launched by aerotow toward Mt Lachens's west face for a mountain flight with a normal climb rate; experienced in mountain flying, he had recently flown long legs on the glider.
2. Goal: 750 km flight: Pilot's planned task was a 750 km cross-country if conditions allowed. Sets the context for the decisions to continue past degraded performance. BEA contributing factor.
3. Unlocked airbrakes deploy in flight: On the LS6 18w the airbrake handle must be shifted right and pulled to unlock; left unlocked, airbrakes can self-deploy. The handle was found closed but unlocked, with a branch in the slot.
4. Immediate sink -6.8, then -9.3 m/s: Recorded sink rates: -6.8 m/s right after release, -7 m/s at 120 km/h crossing a ridge, -9.3 m/s at 130 km/h over a second ridge — matching airbrakes and gear extended, an ~85% glide loss.
5. Sink misattributed to weather: The pilot attributed the descent rate to poor conditions and looked outside regularly, but did not check the airbrake handle or wings despite the extreme sink rates.
6. Skipped La Chapelle safety landing: The pilot was within glide range of the La Chapelle safety area, ~460 m above and 2,000 m out even at the degraded glide ratio, but continued toward the Vallon du Fil hoping for thermals.
7. Out of glide range, low in valley: By the time the pilot turned for the valley, sink had stabilised near 2.5 m/s as airspeed kept falling. No longer in range of a field, he spotted a clearing at 25 m and landed there.
8. Treetop strike, hard landing: At ~85 km/h groundspeed, the glider struck treetops bordering the clearing, then hit the ground hard. The pilot was uninjured; the aircraft was damaged, fuselage and elevator broken.