Glasflügel 304 hits a tree on a valley outlanding after a lee-side downdraft

The pilot of a Glasflügel 304 was seriously injured when the glider, forced into a valley outlanding, hit a tree and the ground; it was destroyed. On a long Alpine task the soaring conditions decayed and the glider lost height in the Maurienne valley. Heading for an aerodrome about 30 km off, the pilot met a strong downdraft on the lee of a steep ridge and lost about 430 m in 75 seconds, putting it out of reach. The narrow valley offered few fields; he chose one late, turned in at about 70 m, then drifted past it, avoided a power line and hit a tree. The lee-side sink removed the aerodrome option and the terrain forced a rushed field choice.

1. Alpine task, sinking air: On a long Alpine flight the soaring conditions decayed and the glider steadily lost height in the Maurienne valley.
2. Lee-side downdraft strips height: On the lee of a steep ridge in a strong valley breeze, a downdraft cost about 430 m in 75 seconds.
3. Aerodrome out of reach, few fields: The loss put the aerodrome about 10 km off beyond glide; the narrow valley offered few landable fields.
4. Late, drifting field approach: He chose a field late and turned in at about 70 m, but wind drift carried him past it and a power line lay ahead.
5. Tree strike: Avoiding the power line, the glider hit a tree then the ground and was destroyed; the pilot was seriously injured.