Kestrel H401 low-altitude alpine impact near Gsteig

The pilot of a Kestrel H401 was fatally injured in a near-vertical nose-first impact onto an alpine pasture ~3.5 km NE of Gsteig during a ridge-soaring flight in the Bernese Oberland; aircraft destroyed. After release from aerotow at Saanen and ridge work along the Eggli–Staldenflüe ridges, the glider was seen at low altitude over the Chrinepass; witnesses described a steep curve followed by a near-vertical descent of about two seconds into a meadow. The last FLARM position was 40 m from the impact site at 1 707 m MSL. Probable cause: acute incapacitation with a stall and spiral dive as consequence.

1. Aerotow from Saanen, ridge work: On 1 August 2011 at 12:37 LT the pilot took off from Saanen in aerotow with the Kestrel H401 D-2197 and was released at 1 770 m MSL at 12:43. He had flown a familiarization flight with a local instructor the previous day at the gliding camp; the instructor described him as a good, untroubled pilot. The pilot had ~922 h on the type and 29:47 h in the last 90 days.
2. Ridge work along Eggli–Staldenflüe: After release the pilot worked the front and back Eggli ridges, gaining ~230 m, then transitioned to the south face of the Staldenflüe (below the Furggespitz) without gaining significant height. At ~13:02 LT he continued the flight along the ridge towards the Chrinepass area.
3. Probable acute incapacitation: Post-mortem examination found severely pre-damaged heart and proximal aorta. The medical analysis identified an acute cardiovascular event leading to incapacitation as the most plausible explanation for the loss of control observed by witnesses. The pilot's most recent medical examination (8 July 2011) had identified no new pathological findings.
4. Low altitude approaching tree group: Witnesses at ~1 640 m MSL saw the glider at low altitude flying towards a group of trees on the slope above the Chrinepass. The average estimated flying height shortly before the departure was about 1 710 m MSL.
5. Steep curve; near-vertical descent: Witnesses described the glider departing from a steep turn and entering a near-vertical, nose-first descent of about two seconds. The motion is consistent with a stall and brief spiral dive at low altitude with no margin to recover.
6. Nose-first impact in alpine pasture: The Kestrel struck the alpine pasture nose-first and slightly past vertical, with the cockpit penetrating deeply into the soft turf; one wing was torn off and thrown ~40 m down the slope. The pilot was fatally injured and the aircraft destroyed. No fire. The last FLARM record at 13:05:36 placed the glider 40 m horizontally from the impact site at 1 707 m MSL.