What happened
On June 3, 2017, at approximately 17:25 local time, a Gardan GY-80-180, registration HB-DVD, was performing a private VFR flight from Langenthal to Lommis. While approaching runway 06, the pilot joined the landing pattern behind another aircraft. The aircraft touched down on the grass runway at a speed of roughly 100 km/h with flaps extended, approximately 80 to 100 meters after the runway threshold.
Following the initial touchdown, the aircraft bounced off the surface. In an attempt to re-establish contact with the ground, the pilot maneuvered the aircraft, but it lifted off again shortly before the end of the runway. The pilot then initiated a go-around by applying full power. However, due to the low airspeed during this maneuver, the aircraft tilted to the right. The right wingtip struck the runway safety area, causing the aircraft to yaw right. The aircraft subsequently impacted the ground on the right main landing gear, followed by the entire landing gear assembly. The impact caused the nose gear to detach, leading the aircraft to tilt onto its left side and strike the left wingtip against the ground. The aircraft continued moving until it overran the runway end and came to a stop on a farm track in an adjacent field.
The investigation
The investigation focused on the sequence of events during the landing and the subsequent loss of control. Investigators examined the aircraft's interaction with the grass runway surface and the physical damage sustained by the airframe, which included significant damage to the engine cowling, propeller, and both wingtips, as well as the loss of the nose gear.
Findings
- The primary cause of the accident was a loss of control following a bounced landing on a grass runway.
- The aircraft's landing gear, characterized by long-travel struts, contributed to the aircraft lifting off the ground again after the initial touchdown due to the uneven surface of the grass runway.
- The low airspeed during the attempted go-around prevented the pilot from maintaining directional control, leading to the wingtip strikes and the eventual overrun.