What happened
During an approach and landing at Cascais aerodrome, a Beechcraft 18 touched down with excessive speed and an improper aircraft attitude, causing the plane to bounce on the first contact with the runway. Following a second touchdown, the aircraft entered a divergent dynamic characterized by successive deviations to the left and right. This sequence resulted in a ground loop, during which the aircraft rotated approximately 220 degrees from its original heading and exited the runway onto the left shoulder. During this excursion, the right wingtip of the Beechcraft 18 struck a Cessna 152 that was holding on the taxiway awaiting takeoff for an instructional flight.
Both crews were uninjured. The Beechcraft 18 sustained damage to the rear fuselage, vertical stabilizers, and rudders after the tail wheel collapsed upon striking the edge of the taxiway. The Cessna 152 suffered substantial damage to its left wing and the cockpit area of the fuselage.
The investigation
The GPIAAF examined the aircraft condition, crew data, and environmental factors at the time of the event. The investigation noted that while some components of the Beechcraft 18 showed signs of degradation likely due to inactivity or lack of preservation, no mechanical failure was identified as the cause of the excursion. The pilot, a 57-year-old holder of a PPL(A) with multi-engine qualification, had not operated this specific aircraft model since 2018. Environmental conditions at the time of landing included a cloudy sky and a wind from 290 degrees at 09 knots, providing an 8-knot right crosswind component for runway 17.
Findings
- The most probable cause of the accident was inadequate piloting technique during landing involving excessive directional correction (PIO).
- A contributing factor was the pilot's reduced proficiency with this specific aircraft model under the reported wind conditions.