Piper PA-46-350P N548C accident near Sanford, Florida

Probable cause

The fatigue cracking at the point the nose landing gear actuator attaches to the mount resulting in separation of the actuator and partial collapse of the nose landing gear. Contributing to the accident was the lack of specific inspection guidance for scheduled maintenance to find and/or identify fatigue cracking in the welded actuator attach points of the newly designed mounts.

NTSB analysis

During landing, as the nose landing gear wheel made contact with the runway, the airplane veered suddenly to the left and exited the runway, incurring substantial damage, before coming to a stop in the adjacent grass area. Examination of the airplane’s nose gear assembly revealed the separation of the nose gear actuator attachment weld tube area (foot) of the motor mount. The metallurgical examination of fractured surface revealed fatigue crack emanating from multiple origins at the exterior of the joint where the attachment foot was welded to the support tube. The motor mount was a new design from the manufacturer which was to eliminate the concerns of fatigue separation of the weld in the foot area which was a problem with the old design motor mounts. The airplane had an annual inspection 36 flight hours prior to the accident. The new design motor mount does not have any specific inspection guidance during scheduled maintenance for identifying fatigue cracking in the actuator attach points. The old design motor mounts had detailed inspection instructions to detect fatigue cracking in the welds of the foot areas.

Text from the NTSB. Open the NTSB docket for ERA09LA471 for the full record.