Event and Flight Sequence
On May 18, 2015, at approximately 07:33 UTC, a Piper PA 23-250 aircraft was preparing for a photographic flight (aerial work) from Bad Vöslau Airport (LOAV), Austria. The pilot, a passenger with flight experience, and a camera operator were on board. After taxiing from the T-hangar to the fuel station, 128 liters of AVGAS were added. The aircraft then proceeded to the holding point of Runway 13, where both engines' magnetos were checked per the flight manual. In takeoff configuration, the pilot initiated a right turn to align with Runway 13. He then applied the main wheel brakes and advanced the throttle levers to full power. Before releasing the brakes, the left main landing gear collapsed, causing the left propeller to contact the asphalt. The pilot shut down the left and then the right engine using the mixture levers. He radioed the airport manager, reporting a gear problem and that the aircraft was immobile near the threshold of Runway 13. The runway was closed, and the rescue chain was activated. All three occupants exited the aircraft unharmed and without assistance.
Aircraft and Crew Information
The aircraft was a Piper PA 23-250 (1974 model, total time approx. 6240 hours, 6257 landings). It was certified and insured. The pilot held a valid CPL(A) with multi-engine, SEP, TMG, and instrument ratings. Total flight experience was about 2987:59 hours, with 19:25 hours on the accident type in the preceding 90 days.
Damage
The aircraft sustained substantial damage. The left main landing gear was deformed toward the left flap, and the left propeller blades showed signs of ground contact. Asphalt marks approx. 40 cm long were found under the left engine nacelle. The left main landing gear tire contacted and deformed the left flap. The left shock strut was angled toward the tail. The nose gear and right main gear were undamaged.
Investigation Findings
Technical examination on site, assisted by an EASA Part 145 approved maintenance organization, revealed that the left main landing gear shock strut had no force-fit connection to the drag strut (overcentering strut). The connecting bolt between the front and rear drag struts was broken. The bolt head and the end with nut and cotter pin were separated by a fracture, located approximately mid-length. Both bolt pieces remained about one-third of their length in the corresponding hole. Spacers intended for the drag struts were found about 3 meters northwest of the aircraft's final position. The landing gear control lever in the cockpit was in the "landing gear down" position; after switching on the battery master switch, the gear position indicator showed "Right and Nose Landing Gear Down."