Accident Summary
On 18 August 2004, a Schempp-Hirth Discus b glider, registration HB-1860, operated by Groupement de vol à voile "Les Martinets", crashed into a wooded slope in the Bois des Léchières, approximately 2 km north of Villars-sur-Ollon, Switzerland, at an altitude of 1800 m. The accident occurred during a VFR training flight departing from Bex aerodrome. The pilot was killed and the glider destroyed.
Flight History
Prior to the flight, the pilot had coffee with an instructor at 13:30 LT and appeared in good health. Later, he seemed annoyed by the absence of the designated tow pilot and proposed to perform a first tow himself. After returning from a second tow flight, he prepared the glider HB-1860. The tow aircraft was a Piper Super Cub with 180 HP. At 15:15, the tow combination departed on runway 33 at Bex, heading toward Collombey. After a left ¾ loop between 900 and 1200 m, they proceeded toward the Chamossaire. At 15:21, over a south-facing slope north of Les Tailles, the pilot released the tow at an altitude of 1900 m without prior announcement. The tow pilot reported light turbulence but no downdrafts. No other glider pilots in the area observed anything unusual about HB-1860.
At 18:30, the duty instructor became concerned because the pilot had indicated he needed to leave by 18:00. A search flight was organized, and the SAR was alerted at 19:47. Night searches were conducted between midnight and 01:45, and the wreckage was located at 09:58 the following day.
Investigation
The Bureau d'enquête sur les accidents d'aviation (BEAA) was notified on 19 August 2004 at 09:55. Investigators were helicoptered to the accident site with assistance from the Vaud canton police. The investigation determined that the glider collided with a wooded slope following a loss of control.
Cause
The cause of the loss of control could not be determined. Contributing factors that may have played a role included a feeling of discomfort by the pilot and a rear center of gravity position.