On November 1, 1986, a Beech 19 (registration N6552R) was involved in an aviation accident near Selkirk, NY. Investigators recorded the probable cause as: The pilot's inability to control the aircraft due to the separation of a control rod caused by inadequate lubrication of the end bearings. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
An aircraft entered an uncontrollable spiral after the left aileron failed. Investigation revealed separated control rod end bearings due to long-term lack of lubrication.
What happened
The pilot attempted to land the aircraft but was unable to maintain directional control due to a failure in the left aileron system. As the aircraft turned to the right, it entered an uncontrollable slow spiral that resulted in impact with the ground.
The investigation
Post-accident examination of the aircraft revealed significant mechanical failures within the flight control system. The failed control rod end bearings showed clear evidence of having not been lubricated for a long period prior to the incident. One control rod, identified by part number 169-524035-3, was found separated at the connection point associated with part number 169-3880082-3.
Findings
The primary factor contributing to the accident was the separation of the control rod caused by a lack of maintenance. The bearings had not been lubricated for an extended time, leading to the mechanical failure that rendered the left aileron inoperative.
Probable cause
The pilot's inability to control the aircraft due to the separation of a control rod caused by inadequate lubrication of the end bearings.