What happened
On May 6, 2008, a Cessna 152, registration CS-DIB, was conducting a solo navigation training flight from Cascais Aerodrome to Santa Cruz Aerodrome. During the landing phase on runway 35, the pilot was performing the flare when the pilot's seat unexpectedly slid backward. This sudden movement caused the aircraft to pitch up aggressively. The main landing gear struck the runway, causing the aircraft to bounce into the air. The pilot was unable to recover control, and the aircraft struck the runway a second time on the nose gear, bouncing once more before the aircraft veered off the right side of the runway and came to rest in the verge.
There were no injuries to the pilot, and the aircraft sustained minor damage to the nose gear.
The investigation
The GPIAAF investigation focused on the pilot's actions and the aircraft's configuration during the approach. The investigation established that the pilot, a student with 59 total flight hours, had performed an unstabilized approach. The investigation noted that the pilot was accustomed to operating at Cascais, and the different runway characteristics at Santa Cruz—specifically a shorter runway, a -1.5% gradient, and an ascending terrain profile—likely caused a perception error regarding the glidepath.
Furthermore, the investigation examined the cockpit configuration and found that the pilot's seat was not properly locked, which was a direct result of an incomplete "Before Landing" checklist. The investigators also noted that the pilot did not utilize engine power to execute a balked landing procedure or to correct the aircraft's attitude following the initial impact.
Findings
- The pilot failed to stabilize the approach, likely due to a lack of familiarity with the specific terrain and gradient of the Santa Cruz runway.
- The pilot failed to execute the "Before Landing" checklist, resulting in the unsecured pilot seat.
- The sliding seat caused a sudden change in the aircraft's center of gravity and attitude during the flare.
- The pilot did not apply the necessary power or maneuvers required for a balked landing to recover from the initial bounce.