What happened
On June 14, 2023, at 04:58 UTC, a Piper PA-34-220T (Seneca IV), registration OE-FST, was performing a VFR approach to runway 22 at Bratislava Airport (LZIB) after departing from Piešťany (LZPP). The pilot in command executed a smooth touchdown on runway 22. However, shortly after the nose gear made contact with the runway surface, the aircraft began to veer to the right. Despite corrective rudder inputs, the nose of the aircraft dropped, and the aircraft continued to taxi on its main landing gear for approximately 300 meters before coming to a stop near the right edge of the runway.
The pilot sustained no injuries, but the aircraft suffered extensive damage, including significant damage to the forward lower fuselage composite skin and all propeller blades.
The investigation
The investigation focused on the mechanical state of the landing gear and the hydraulic system. During inspections, investigators found that while the landing gear lights in the cockpit indicated the gear was extended and locked, the main landing gears actually locked only when the aircraft was tilted upward during testing. In contrast, during the actual landing, the aircraft was in a nose-down attitude.
Furthermore, the investigation revealed that the nose gear could not fully extend due to a damaged guide rail. Upon removal of this rail, the gear was able to extend and lock properly. Regarding the hydraulic system, investigators found that the hydraulic fluid level in the integrated reservoir of the electric hydraulic pump was below the required minimum. There was evidence of a leak at the junction between the integrated reservoir and the pump body, which caused fluid to accumulate in the area under the pump.
Findings
- The nose gear failed to lock in the extended position during the landing phase.
- The insufficient hydraulic fluid level caused by a leak between the integrated reservoir and the hydraulic pump likely led to air entering the hydraulic system, preventing the gear from fully locking.
- A damaged guide rail prevented the full extension of the nose gear during the incident.
- The cockpit's green gear lights may have provided misleading indications because the microswitches were in a closed position even when the gear was not fully locked due to the aircraft's pitch attitude.