DG-400 stalls after first self-launch with engine left extended

A DG-400 was destroyed and the pilot seriously injured on a first self-launch on type, impacting forest east of the airfield near Moenchsheide (Germany). The pilot had 180 h total with 46 minutes on type from two prior aerotow flights, and his only 11 self-launches had all been on two-seaters. After a normal self-launch from RWY 28 he shut down the engine mid-downwind at about 450 m AGL but did not retract it. Witnesses saw the glider flown apparently slow northwest of the field. From about 150 m AGL it rolled right and dropped near-vertically. No technical defects were identified.

1. Self-launch RWY 28, 1st on type: At 13:24 LT on 18 May 2015 the pilot began his first self-launch on this DG-400 from RWY 28 at the Segelfluggelände Mönchsheide (elevation 672 ft AMSL, 700 m grass strip). The aircraft had been refuelled with 20 litres before the flight.
2. 46 min on type, novice self-launcher: The pilot held a glider licence with 180 hours total experience and only about 1.5 hours in the prior 90 days. He had 46 minutes on the DG-400 over two prior aerotow launches — one the day before and one in September 2014. His 11 prior self-launches had all been on two-seater types; this was his first self-launch on a single-seater.
3. Engine off mid-downwind, not stowed: The self-launch and initial climb were normal. Witnesses saw the engine shut down at about the middle of the downwind leg. The pilot did not retract it. FLARM-based reconstruction shows the aircraft climbed to about 450 m AGL in the circuit area before continuing in straight flight. The extended powerplant continued to produce drag.
4. Apparently slow NW of airfield: After flying straight on 130° losing height, then a 90° turn north-west of Bad Breisig onto 220°, a right turn in the extension of the runway baseline and a further leg to the north-west, witnesses observed the glider being flown at apparently too low a speed north-west of the airfield.
5. Rolls right at ~150 m, vertical drop: From about 150 m AGL the aircraft rolled right and entered a very steep, almost vertical descent toward the woodland east of the airfield.
6. Vertical impact in forest: The DG-400 struck the forest nearly vertically. The left wing broke at the first tree contact and remained in the canopy; the aircraft came to rest inverted on the forest floor, the empennage twisted off. The engine was found extended, gear retracted, main switch ON, ignition OFF, fuel cock open. No technical defects were found. The pilot was seriously injured.