Undetected fatigue crack in landing gear system contributed to the January 2014 runway excursion of an aircraft in Alma, Quebec

DORVAL, QC, March 26, 2015 /CNW/ - The Transportation Safety Board of Canada (TSB) today released its investigation report (A14Q0011) into the runway excursion of a Piper Malibu Mirage aircraft in Alma, Quebec.

On 23 January 2014, a privately operated Piper Malibu Mirage aircraft departed Montréal International (Mirabel) Airport for Alma, Quebec, with a pilot and one passenger on board. The flight was uneventful until the landing when the nose wheel contacted the runway and directional control was lost. The aircraft veered left and departed the runway surface 400 feet after the loss of control. The aircraft came to a stop about 100 feet from the runway edge in a compacted snow bank. There were no injuries. The aircraft was substantially damaged.

During the approach, the pilot selected the landing gear down and was provided with an indication in the cockpit that all three landing gears were down and locked. However, the nose gear was not fully down and locked, so the unaware pilot continued with the landing. This accident sequence is consistent with an equipment failure. The part that failed was the landing gear component of the engine mount. It prevented the nose gear from extending fully forward.

The investigation revealed that the right-side nose landing gear component of the engine mount fractured mainly in overstress from a pre-existing fatigue crack. The inspection criteria dictated an examination at 740 flying hours; however, that type of crack may appear before the original scheduled inspection period. On 5 June 2014, Piper Aircraft issued Service Bulletin (SB 1103E) changing the inspection period to 200 hours. The investigation noted that if the requirements prescribed in SB 1103E are not made mandatory for private operators in Canada, there is a continued risk that fatigue cracks may not be discovered in a timely manner.

The TSB is an independent agency that investigates marine, pipeline, railway and aviation transportation occurrences. Its sole aim is the advancement of transportation safety. It is not the function of the Board to assign fault or determine civil or criminal liability.

SOURCE Transportation Safety Board of Canada