On September 2, 1991, a North American AT-6D (registration N3660V) operated by Richard D. Tabery was involved in an aviation accident near Hayward, CA. Investigators recorded the probable cause as: THE FAILURE OF THE PILOT TO MAINTAIN DIRECTIONAL CONTROL OF THE AIRCRAFT WHILE CORRECTING AN UNWANTED DEVIATION. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
Aircraft touched down smoothly on wheels, but the right landing gear strut collapsed during rollout, causing a wing drop and ground loop that resulted in collapse of the landing gear.
What happened
The pilot reported that the initial touchdown was executed as a smooth wheel landing. During the subsequent rollout phase, the right landing gear strut unexpectedly lowered. This mechanical failure caused the right wing to drop abruptly, initiating an uncommanded turn to the right.
In response, the pilot applied left aileron and rudder input along with power adjustments in an attempt to correct the yaw and maintain directional control. However, the corrective inputs were insufficient to prevent further deviation. The left wing subsequently struck the ground, leading to a ground loop. The sequence of events concluded with the collapse of the landing gear.
The investigation
The available source material provides only the pilot's narrative of the event. No additional mechanical examination results or investigative findings are included in the provided text to explain the strut failure.
Findings
The right landing gear strut lowered during rollout after a smooth wheel landing.
The aircraft experienced an uncommanded turn to the right due to the wing drop.
Pilot attempts to correct the turn using left aileron, rudder, and power were unsuccessful in preventing ground contact.
The left wing contacted the ground, resulting in a ground loop.
The landing gear collapsed as a result of the ground loop and structural stress.