What happened
While performing an NDB approach under instrument meteorological conditions, the crew of the aircraft experienced a fire warning light indicating an issue with the right engine. At the time of the warning, the landing gear was already in the extended position. In response to the alert, the pilots shut down the right engine and began a missed approach procedure. Following the engine shutdown, the crew encountered significant mechanical difficulties, as the landing gear failed to retract and the aircraft struggled to maintain its altitude.
As the aircraft descended into an overcast layer at approximately 600 feet, the crew attempted to restart the right engine, but the effort was unsuccessful. The aircraft continued to descend through the cloud layer, reaching an altitude between 150 and 170 feet. The instructor pilot subsequently performed an emergency landing in an open field. During the landing sequence, the nose gear struck soft soil, causing the aircraft to nose over.
Findings
Post-accident investigations determined that the primary cause of the electrical malfunctions was a chafed electrical power jumper wire located between two bus bars. This chafing caused a short circuit, which triggered the false engine fire warning. Additionally, the electrical failure caused the left and right isolation circuit breakers, as well as the bus tie circuit breaker, to trip into the open position. This electrical fault was also responsible for the failure of the landing gear retraction mechanism.