What happened
On October 22, 2010, a Piper PA 34-220T, registration D-GACR, was performing a takeoff from runway 13 at M. R. Štefánik Airport (LZIB) in Bratislava, Slovakia. The flight was planned from Bratislava to Wiener Neustadt/East (LOAN) under VFR conditions. During the takeoff roll, at a speed between 6/5 and 75 KTS, the aircraft experienced an uncontrolled tilt to the left. This resulted in the left wing making contact with the runway surface. Following the impact, the aircraft's nose pitched up to an altitude of approximately 3 to 4 meters. The crew managed the emergency by maintaining the takeoff direction, setting the propellers to idle, and shutting down the engines. The aircraft subsequently landed back on runway 13, coming to a stop on the right side of the centerline with the landing gear in an intermediate position within the retraction cycle. There were no injuries to the two crew members.
The investigation
The investigation focused on determining why the landing gear retracted without pilot input during the takeoff roll. Investigators examined the aircraft's landing gear control system using an external power source to simulate operation. During testing, the investigators observed excessive current draw, indicated by a drop in cockpit instrument brightness and a high reading on the ammeter, which caused the circuit breaker to trip. Upon dismantling the plastic cover of the landing gear position controller, investigators discovered a loose screw and washer (part number MS35206C216 and MS35337-70) resting directly on the electrical contacts of the controller.
Findings
- The crew held valid licenses and followed standard takeoff procedures.
- The aircraft was airworthy and showed no mechanical malfunctions prior to the flight.
- A loose screw and washer located on the landing gear controller contacts caused a short circuit, leading to the spontaneous retraction of the landing gear during the takeoff roll.