What happened
On May 28, 2017, at approximately 09:58 LMT, a Cessna 185A, registration SP-AKZ, operated by Aeroklub Kielecki, was performing a skydiving flight at Masłów Airport (EPKA). After completing two training circuits to refresh flight habits, the pilot and four skydivers prepared for departure.
During the initial phase of the takeoff roll, the pilot applied maximum engine power. At this moment, the pilot's seat suddenly slid backward, causing the pilot to lose control of the rudder pedals. In response to the sudden movement, the pilot instinctively pulled back on the control yoke and reduced engine power. The aircraft veered approximately 220 degrees from its intended path and came to a stop about 80 meters from the start of the takeoff roll. There were no injuries to the pilot or the passengers, though the aircraft sustained significant damage, including a broken landing gear leg, damaged engine mounts, and warped fuselage skin.
The investigation
The PKBWL investigation focused on the seat's mounting mechanism and the pilot's pre-flight checks. The investigation established that the pilot, being of short stature, had moved the seat as far forward as possible to ensure full rudder pedal reach. In doing so, the seat was positioned at a point where the left mounting pin could be dislodged from its rail.
Investigators found that the pilot had attempted to verify the seat's security by pressing his feet against the rudder pedals. Due to the asymmetrical deformation of the seat frame, the locking pin remained under enough pressure to create a false sense of security. Furthermore, the investigation revealed that the inertial safety mechanism, designed by the manufacturer to prevent the seat from sliding backward, was non-functional. The end of the safety belt had been improperly attached to a seatbelt anchor point instead of the floor mounting.
Findings
- The pilot error in failing to properly lock the seat in a secure position.
- The seat was positioned at the extreme forward limit of the rails, making it vulnerable to dislodging.
- The inoperative inertial safety mechanism failed to prevent the seat from sliding.
- The safety belt was incorrectly attached to a seatbelt anchor rather than the intended floor mounting.
- The pilot's pre-flight check (pressing pedals to verify seat stability) provided a false indication of a secure lock due to spring tension in the seat frame.