What happened
The pilot was conducting a departure from the airport under marginal visual meteorological conditions. During the initial climbout phase, the aircraft experienced a sudden loss of engine power. Unable to maintain altitude or continue the climb, the pilot initiated an emergency return to the departure airport for a single-engine approach and landing.
Upon touchdown, the airplane impacted the runway surface with significant force and veered off the paved area. The incident occurred during the landing phase of the flight, concluding the sequence that began with the mechanical failure shortly after takeoff.
The investigation
Following the accident, investigators conducted a thorough examination of the aircraft's propulsion system to determine the root cause of the power loss. The inspection focused on the internal components of the engine, specifically looking for signs of mechanical failure or obstruction.
The examination revealed that the intake valve for the number three cylinder was stuck in the open position. This mechanical fault prevented proper combustion and airflow within that cylinder, leading to a significant reduction in engine performance and the subsequent loss of power during the critical climbout phase.