What happened
On August 14, 2016, at approximately 18:20 UTC, an L 410 UVP-LW, registration OM-DAC, was performing a series of VFR parachute jumps at Kolín Airport (LKKO). Following the final jump of the day, the crew began a descent to the airfield. During the approach to runway 03R, the pilot flying (PF) requested the extension of flaps to 15 degrees.
As the aircraft approached the threshold, the pilot flying decided to transfer control to the pilot not flying (PNF) using the phrase "YOUR CONTROL." This transfer occurred during the final approach phase, bypassing the standard "Final Check" procedures. The aircraft maintained a high approach speed of approximately 190 km/t and performed a maneuvering turn to touchdown. Upon contact with the runway, the aircraft did not brake effectively and began to veer right, eventually coming to a stop in the grass adjacent to the runway.
The investigation
The ÚZPLN investigation established that the aircraft's landing gear remained in the retracted position during the landing. The inspection of the aircraft immediately following the incident revealed that the "GEAR DOWN" warning light was illuminated and the landing gear lever was in the "UP" position. The impact caused damage to the main landing gear fairings, the nose gear bay covers, and various antennas on the lower fuselage.
The investigation examined the crew's actions, the aircraft's technical state, and the meteorological conditions. It was noted that the crew had been conducting jumps for nearly 11 hours that day. While the aircraft was technically airworthy and the weather conditions were suitable for VFR flight, the investigation focused on the failure to follow established checklists.
Findings
- The primary cause of the incident was the crew's failure to extend and verify the landing gear position because they did not complete the required landing checklist.
- The crew's attention was diverted during the final approach due to the unexpected transfer of control from the pilot flying to the pilot not flying.
- The pilot not flying likely neglected to extend the gear after the final jump, and neither pilot verified the gear position during the descent.
- The landing gear warning siren and lights likely failed to alert the crew because the specific operational conditions for the warning (such as engine power settings or airspeed) were not met at the time the flaps were extended.
- A contributing factor was likely fatigue, resulting from the high number of jumps performed and the long total duty time of the crew.