First solo: pitch oscillation grows, ASK 13 stalls into houses

An ASK 13 was destroyed and a student pilot fatally injured during a first solo, with the glider striking a row of houses about 500 m north of the airfield (Germany). Training had begun 14 days earlier with 67 dual flights and about 9 h total. After a normal winch launch the student flew the downwind at low airspeed. A pitch oscillation between 61 and 91 km/h developed and amplified despite an instructor radio call to lower the nose. The glider pitched near-vertical, stalled, and rolled off a wing. Theoretical training was inadequate, abnormal flight states were not sufficiently practised, and a second instructor's solo approval was missing.

1. First solo: winch launch from RWY 28: At 19:13:15 LT on 4 August 2012 a student pilot began a winch launch from RWY 28 of Flugplatz Quakenbrück on the first solo flight. The cable was released at about 329 m AGL after a normal launch. Wind was light, evening conditions were calm, no thermal influence. The student had begun glider training 14 days earlier on 21 July 2012 in a club introductory course and had accumulated 67 launches with an instructor totalling about 9 h. Five dual flights had already been flown earlier that day; this was the last student of the course not yet solo.
2. Insufficient training before solo: BFU identified several training shortcomings before the solo. Theoretical instruction during the 14-day course was inadequate (one documented introductory hour plus one further theory morning, against the nine units historically required for the A-section). Abnormal flight-attitude exercises, spinning and steep-spiral recovery had been started on the second training day, before the student had the practical or theoretical foundation. The second instructor's solo approval was given orally on an earlier day, not on the day of the solo and not after a final check flight under simulated solo conditions, contrary to the DAeC methodology.
3. Low downwind speed, oscillation begins: On the downwind leg of the circuit ground speed sat at an unusually low 61–76 km/h (vs ~85 km/h for normal cruise in this type, possibly aggravated by a nose-down trim setting). A heading change from 025° to 005° suggested early task saturation. From 19:14:43 LT, FLARM data show a pitch oscillation beginning, speeds varying 61–91 km/h, altitude swings of tens of metres.
4. Oscillation amplifies (61–91 km/h): The oscillation amplitude grew. Sink rates reached 5.5, then 9.2, then 7.8 m/s on successive cycles between roughly 240 m and 100 m AGL. Speed alternated between 61 and 91 km/h. The student's control inputs reinforced rather than damped the pitch motion.
5. Radio call; student overloaded: The instructor transmitted a radio instruction to 'put the nose below the horizon'. BFU concluded the student was overloaded by the oscillation and the workload it created; the radio instruction was not effectively converted into stabilising control inputs. Injuries to the right hand suggest the student was still gripping the stick at impact, possibly with elevator held fully back at the end.
6. Stall after vertical climb; hits houses: At low altitude the ASK 13 pitched into a near-vertical climb, stalled, and dropped over the left wing. It descended into a residential / industrial area about 500 m north of the airfield, contacting the first house of a row at 5.5 m above the pavement and shedding parts of the left wing through windows and along the row before coming to rest inverted on the paved parking area of the fourth house. The student was fatally injured.