What happened
On October 6, 2024, at approximately 12:00 LT, an L-13 SW VIVAT, registration HA-1290, was performing a private VFR flight departing from runway 29 at Dunakeszi Airfield. During the takeoff roll, the pilot observed a Scheibe SF-25 Falke glider taxiing ahead. Seeking to overtake the slower aircraft, the pilot requested and received permission to depart first. In the haste to execute this maneuver, the pilot failed to verify that the canopy was properly locked.
After liftoff and reaching an altitude of approximately 50 meters, the aircraft's canopy suddenly opened. The sudden airflow caused documents and items to be sucked out of the cockpit, creating significant chaos. The pilot attempted to manually close the canopy without success. While attempting to manage the aircraft, the pilot reduced engine power to transition from a climb to level flight; however, this maneuver, combined with the increased drag from the open canopy, led to a loss of airspeed and a developing stall. The aircraft's right wing dropped, and it entered a 180-degree turn before striking an industrial container located near the airfield. The pilot sustained one serious injury.
The investigation
The KBSZ investigation examined the aircraft's structural integrity, the pilot's pre-flight procedures, and the flight dynamics following the canopy failure. Investigators reviewed OGN Tracker data, analyzed video footage from a nearby industrial camera, and interviewed the pilot and witnesses. The investigation also looked into the aircraft's maintenance records and the pilot's training background.
Findings
- The primary cause of the accident was the failure to verify the canopy locking mechanism due to haste during pre-flight and taxiing procedures.
- The pilot did not utilize a physical checklist, relying instead on memory, which allowed critical steps—such as checking the canopy locks and setting the correct barometric pressure—to be omitted.
- The sudden opening of the canopy created an intense cockpit environment characterized by high stress, wind turbulence, and flying debris, which distracted the pilot from flight controls.
- The decision to reduce engine power during a critical phase of flight, following the canopy failure, contributed to the loss of airspeed and the subsequent stall.
- Factors such as the impact with vegetation and the container structure helped mitigate the energy of the crash, likely preventing a more fatal outcome.