Discus bT hits trees short of outlanding after sustainer fails to start

The pilot of a Discus bT was seriously injured when the glider struck trees short of an outlanding field at Spaichingen; aircraft destroyed. Shortly after a winch release at Klippeneck the pilot extended the sustainer to test it, but it would not start. The glider headed south-west, losing height as further start attempts continued with the engine deployed. From ~170 m AGL the pilot turned toward a field; the approach height was insufficient and the glider, descending steeply with engine extended, struck trees on a 3 m embankment and overturned. The probable cause was misjudgement of the outlanding while attempting to restart the sustainer.

1. Winch launch from Klippeneck: The pilot launched the Discus bT by winch from RWY 23 at the Klippeneck gliding site.
2. Sustainer fails to start after release: Shortly after release the pilot extended the sustainer to test it; the starter cranked but the engine did not run. A return to the airfield was no longer possible from the height available.
3. Height lost during start attempts: The glider tracked south-west, descending continuously while the pilot made further start attempts with the engine deployed; after about three minutes, height had reduced to about 170 m AGL.
4. Turn toward outlanding field: From the descending flight path the pilot turned left at ~170 m AGL toward a selected outlanding field, while still attempting to restart the engine.
5. Engine extended, increased sink rate: With the sustainer still deployed the drag was higher than in clean configuration, steepening the approach and reducing the glide reach.
6. Trees struck on embankment; overturned: On approach from the west, the glider struck trees on a vegetated embankment; the left wing was severed and it overturned into a field. The pilot was seriously injured, the glider destroyed.