Cessna 172R N819KS accident near Santa Monica, California

Probable cause

A failure of the nose wheel upper torque link bolt, which resulted in a loss of steering control. Contributing to the accident were maintenance personnel’s failure to inspect and replace the fractured bolt and the pilot’s oversight of the bolt during his preflight inspection.

NTSB analysis

The pilot was completing a maintenance flight to determine that the airplane was airworthy after repairs following a collision with a fuel truck that had taken place one month before the accident. The high-speed taxi test and subsequent flight in the airport traffic pattern were uneventful. However, when the pilot landed the airplane, the nosewheel began a shimmy that intensified as the airplane slowed. The airplane began to veer left, and the pilot attempted to correct the movement with right rudder, aerodynamic braking, and then both brakes, but the airplane nosed over and came to rest inverted, which resulted in substantial damage to the rudder.

A bolt from the upper portion of the nose torque link was found on the runway and a poastaccident material analysis revealed that the bolt had separated from shear overstress. The investigation also found that the bolt had been damaged and was not replaced as part of the repairs made to prepare the airplane for the ferry flight following the previous collision with the fuel truck.

The accident was the result of a failure of the upper torque link during landing. The link failed due to a bolt that had unaddressed fractures originating from when the airplane collided with the truck. This resulted in a loss of steering control and a subsequent loss of directional control on the ground. A video provided by the airplane owner of the airplane showing the damage on the airplane following the collision with the fuel truck clearly shows the bent upper torque link bolt.

Text from the NTSB. Open the NTSB docket for WPR23LA216 for the full record.