What happened
On June 4, 2010, a Rolladen-Schneider LS1-f glider, registration D-866ARG, was performing local flight maneuvers at Covilhã Aerodrome. The aircraft had been towed by a SOCATA MS.893A Ralley Commodore 180 and had been airborne for approximately two and a half hours.
While flying the circuit for runway 16, the pilot encountered strong downdrafts. In an attempt to manage the loss of altitude, the pilot decided to initiate a turn to the final approach early. However, the loss of lift was significant enough that the aircraft could not maintain sufficient altitude to clear the threshold. During the maneuver, the right wing of the glider struck the wire fence surrounding the aerodrome. The impact caused the aircraft to veer and strike the ground with significant force, resulting in the separation of the tail section. The pilot escaped the wreckage without injury.
The investigation
The GPIAA investigation examined the flight history, meteorological conditions, and the physical wreckage. Investigators noted that the aircraft's right wing showed delamination along its length due to the impact with the fence. The investigation also reviewed the pilot's flight experience and the environmental factors present at the time of the accident. Meteorological data indicated variable southeasterly winds with gusts and clear skies, but confirmed the presence of downdrafts near the approach to runway 16.
Findings
- The primary cause of the accident was the collision of the right wing with the perimeter fence preceding runway 16.
- The presence of strong downdrafts during the approach contributed to the loss of altitude.
- The pilot's limited flight experience, with only 43 total flight hours, contributed to an inadequate calculation of the timing required for the turn and the necessary clearance from the ground.