What happened
On October 17, 196 and, a Bücker Bü 133 U-88 performed a routine landing on runway 07 at the Porrentruy aerodrome. While the initial touchdown was aligned with the runway, the aircraft began to drift toward the left side of the strip during the landing roll. As the aircraft veered off the marked area, it struck a marker canister and crossed a drainage ditch. The impact with the ditch caused the landing gear to collapse, forcing the aircraft to come to a halt on its fuselage and lower wings. The pilot escaped the wreckage uninjured, though the aircraft sustained significant damage, including a broken wooden propeller and structural deformation to the fuselage and wings.
The investigation
The investigation focused on the pilot's control of the aircraft during the landing roll and the visibility challenges inherent to the aircraft type. The pilot, who had recently obtained his private pilot license, had primarily trained in tricycle-gear aircraft such as the Cessna 150, which offer much better forward visibility. While the pilot had performed several training sessions in the Bücker Bü 131, this flight in the single-seat Bücker Bü 133 was his first solo operation in a tailwheel-configuration aircraft. Investigators noted that the pilot had focused his attention on the right side of the airfield, looking toward the parking area and buildings, and failed to monitor the left side of the aircraft's path.
Findings
- The pilot failed to maintain adequate directional control of the aircraft during the landing roll.
- Inadequate scanning of the surroundings led the pilot to remain unaware that the aircraft was deviating from the runway centerline.
- The pilot's previous flight experience was almost exclusively in nosewheel aircraft, which do not present the same forward-visibility limitations as tailwheel aircraft.
- The pilot's visual focus was restricted to the right side of the taxi path, neglecting the left side where the ditch and runway edge were located.