Casualties unknown

1996-11-01: Cessna 172RG (N9520B) — Spartan School OF Aeronautics — Tulsa, OK

Tulsa, OK, US

On November 1, 1996, a Cessna 172RG (registration N9520B) operated by Spartan School OF Aeronautics was involved in an aviation accident near Tulsa, OK. Investigators recorded the probable cause as: The failure of the main landing gear pivot gear assembly. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive; 3 related events involving the same aircraft type or operator are linked below.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 1781061362Data APIEditorial standards

A witness reported a smooth touchdown with no side load, but the right main landing gear collapsed, causing the aircraft to skid off the runway. Examination revealed a fractured pivot assembly with overload evidence and small cracks.

Incident Description

According to a witness, the airplane flared smoothly and touched down with what appeared to be no side load. As the aircraft settled onto the runway surface, the right main gear collapsed, and the aircraft subsequently skidded off the right side of the runway.

Examination Findings

During examination of the right main landing gear, it was discovered that the gear pivot assembly was fractured adjacent to the spline. It has not been determined whether the fracture occurred during gear retraction, extension, or upon contact with the runway. Visual inspection of the fractured surface showed evidence of overload, however a small area on the outer portion of the surface had several small cracks bordering the edge. The failed pivot assembly, part number 2441100-9, had a total time of 1,611.8 hours.

Maintenance History

According to maintenance records, Cessna Service Bulletin SE390.1, dated April 20, 1990, was applicable to this aircraft and was complied with. The purpose of the Service Bulletin was to inspect main landing gear pivot assemblies for cracks in the spline area.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20001208X07032. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.