What happened
On 16 November 2024, a Morgan Cougar Mk 1 aircraft, registered VH-LDV, departed from West Sale Airport in Victoria for a local flight. The aircraft was carrying a pilot and two passengers. Approximately 17 minutes into the flight, while performing a series of orbits, the aircraft collided with terrain in a paddock located roughly 19 km north-north-west of the airport. The impact resulted in the destruction of the aircraft and 3 fatalities.
Flight path analysis showed that as the aircraft entered its final turn, its airspeed and altitude were steadily declining. The aircraft transitioned from a groundspeed of 103 kt at 716 ft to 64 kt at 269 ft. During this maneuver, the aircraft maintained a steep bank angle of approximately 45 degrees. Data and witness accounts indicated that the aircraft suddenly pitched nose-down, appearing to fall from the sky. The investigation determined that the aircraft entered an accelerated stall during this steep turn at an altitude that left no margin for recovery.
The investigation
The ATSB examined the wreckage and flight data, finding that the engine was operational at the time of impact and the aircraft was attempting to recover to level flight. This ruled out mechanical failure as a cause.
Further investigation into the pilot's training revealed significant knowledge gaps regarding aerodynamics. A review of the pilot's recent examination records showed failed attempts on the RAAus theory exam, specifically regarding the relationship between load factor, angle of bank, and stall speed. The pilot failed to grasp how increased load factors in maneuvering flight raise the stall speed.
Findings
- The primary cause was an accelerated stall occurring during a steep turn at an insufficient height for recovery.
- The pilot likely lacked a sufficient understanding of how maneuvering flight affects stall speeds, which contributed to the decision to perform slow, steep turns.
- Management practices at the flight training school did not provide adequate oversight to ensure graduates possessed the necessary aeronautical knowledge.
- The RAAus examination system lacked sufficient controls to ensure members achieved the required syllabus knowledge.
- The aircraft design lacked energy-attenuating features in the landing gear and seating, and the fuel tank placement contributed to a post-crash fire.
- The use of car-style seatbelts in the front seats led to occupants being ejected during the impact.