On July 1, 1990, a Cessna 340 (registration N5411M) operated by Benech, Edmond A. was involved in an aviation accident near Salinas, CA. Investigators recorded the probable cause as: Maintenance personnel inadvertently disconnected the landing gear retract/extend linkage during servicing three hours prior to the accident, leaving the attaching hardware loose in the wheel well. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
The right main landing gear collapsed upon touchdown after maintenance personnel inadvertently disconnected the retract/extend linkage, leaving hardware loose in the wheel well.
What happened
During the landing phase of flight, the aircraft's right main landing gear failed to support the weight of the plane, resulting in a collapse. The incident occurred immediately upon contact with the runway surface.
The investigation
Examination of the aircraft revealed that the linkage responsible for retracting and extending the landing gear was disconnected. Investigators located the attaching hardware, including nuts and washers, loose within the wheel well area. Further review of maintenance records indicated that this disconnection occurred during servicing performed just three operational hours prior to the accident.
Findings
The failure was directly linked to improper reassembly following recent maintenance work. The critical linkage had been left disconnected by the maintenance crew, and the associated hardware remained unsecured in the wheel well rather than being properly installed or removed from the aircraft entirely.
Probable cause
Maintenance personnel inadvertently disconnected the landing gear retract/extend linkage during servicing three hours prior to the accident, leaving the attaching hardware loose in the wheel well.