Primary finding
Probable cause
Failure of the engine mount which resulted in a collapse of the nose landing gear.
Investigator assessment
Analysis narrative
According to the pilot, while on final approach, he confirmed that he had the flaps down and three green lights indicating the landing gear was down and locked. He touched down on the main landing gear and then the nose gear while using the rudder pedals to maintain directional control. Shortly after, the pilot noticed that the airplane was yawing to the left and the rudder pedals were no longer effective. The nose landing gear had collapsed, and the airplane departed the left side of the runway into a ditch, which resulted in substantial damage to the left wing. Postaccident examination of the airplane revealed a broken engine mount where the nose landing gear retract cylinder was located. About 10 years before the accident, the airframe manufacturer issued a service bulletin requiring inspection of this area for cracking after each 100 hours of flight time. The bulletin described that, “Cracks may develop in the area of the nose gear actuator attach feet on the engine mount. This condition can occur when the nose landing gear is subjected to excessive loads due to hard landings, rough field operations, excessive speed turns, improper airplane towing (sudden, aggressive starts and stops), or other improper operations.” The mechanic who performed the last annual inspection stated that he had not completed the inspection specified by the service bulletin and that the airplane had accumulated 138 hours of flight time since the last compliance. Whether the nose landing gear collapse that occurred during the accident flight was the result of previous, undetected cracking or the landing on the accident flight was not determined.