Incident Overview
The airplane departed the left side of the runway during the landing roll. Upon impact with a snow bank, the nose landing gear collapsed. The pilot reported that the main landing gear touched down normally, but when the nose wheel contacted the runway, the airplane yawed violently left. The pilot believed the nose gear steering was unresponsive to control inputs.
Evidence and Examination
Tire and skid marks on the runway matched the pilot's description, showing the airplane's track diverging more than 70 degrees from the centerline immediately after nose wheel touchdown. The nose tire exhibited scrub marks perpendicular to the tread from right to left. No abnormal wear or flat spots were found on the main tires or brakes.
Post-accident inspection of the nose gear system found a sheared bolt connecting the hydraulic actuator to the engine mount, and a fractured nose gear steering arm. Both components were determined to have failed due to overload. The steering bungee showed no anomalies. The steering arm met manufacturer specifications.
Manufacturer Information
According to the airplane manufacturer, there had been 32 prior reports of temporary, unexplained loss of directional control immediately after nose wheel touchdown, primarily during crosswind conditions or when applying full propeller reverse. The manufacturer's engineering investigation concluded that insufficient nose gear steering authority contributed to these events; the system could allow the nose gear to momentarily exceed pilot input. In response, the manufacturer issued a service bulletin recommending nose gear installation modifications to increase steering authority. The accident airplane was built after these modifications were implemented on the production line.