What happened
On May 25, 2016, at 09:25 UTC, a collision occurred on the apron of Leoš Janáček Airport in Ostrava involving a Zlín Z 43, registration OK-XOD, and a parked Cessna C 152, registration OK-LFA.
As part of his flight training, a student pilot was instructed by his instructor to enter the cockpit of the Zlín Z 43, perform checks, start the engine, and warm it up. The instructor remained outside the aircraft, attending to another student. Upon starting the engine, the power increased unexpectedly to high RPMs, causing the aircraft to begin moving forward. The student pilot was unable to stop the movement, and the aircraft traveled approximately 100–120 meters across the apron.
The moving Zlín Z 43 struck the stationary Cessna C 152, which was parked without wheel chocks. The impact caused significant damage to both aircraft: the propeller of the Zlín struck the rear fuselage of the Cessna, causing the tail section to separate, and the Zlín's cockpit frame subsequently struck the Cessna's wing. The collision ended when the Zlín's propeller became embedded in the Cessna's engine compartment, forcing the engine to stop. There were no injuries to the student pilot or any ground personnel.
The investigation
The ÚZPLN investigation examined the training procedures, the mechanical state of both aircraft, and the actions of the crew. The investigation established that the Cessna C 152 was parked in accordance with local regulations but lacked wheel chocks. The Zlín Z 43 was also parked without chocks.
Technical inspections of the Zlín Z 43 following the accident revealed no functional defects in the brakes, engine controls, or ignition systems. However, it was noted that the engine control lever mechanism had a tendency to move forward when the lock was released, which could cause an increase in RPM. The student pilot reported that he attempted to use the brakes to stop the aircraft, but they did not respond effectively during the sudden surge.
Findings
- The student pilot failed to follow established engine start procedures, specifically failing to verify the position of the throttle lever and failing to depress the brake pedals.
- The instructor overestimated the student's ability to handle the engine start independently and was not present in the cockpit to intervene.
- The student pilot likely failed to react adequately to the sudden surge in engine power due to the shock of the event.
- The distance between the two aircraft at the time of the start was sufficient to allow for a safe stop if the engine had been shut down or the brakes applied correctly.
- Neither aircraft was secured with wheel chocks at the time of the incident.