On October 23, 1993, a Cessna 170 (registration N3975V) was involved in an aviation accident near Williamstown, NJ. Investigators recorded the probable cause as: Fatigue cracking at the junction of the flange and main landing gear axle led to the failure and separation of the axle. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
An airplane experienced a left main landing gear axle separation during takeoff roll after traveling about 150 feet, causing a swerve and nose-over. Investigation found fatigue cracking at the flange-axle junction.
Event Description
The airplane commenced its takeoff roll and had covered approximately 150 feet when the left main landing gear axle separated from the aircraft. This separation caused the airplane to swerve to the left. Subsequently, the airplane nosed over. The event took place during the initial ground acceleration phase of the takeoff.
Investigation Findings
An investigation was conducted to determine the cause of the axle separation. The examination revealed that fatigue cracking had developed at the junction of the flange and the main landing gear axle. This fatigue cracking directly resulted in the failure of the axle. Once the axle failed, the landing gear assembly separated from the airplane. The crack originated at the flange-axle interface and propagated through the axle material until structural integrity was lost. The fatigue cracking compromised the axle's ability to withstand the loads encountered during the takeoff roll, leading to fracture and separation.
Probable cause
Fatigue cracking at the junction of the flange and main landing gear axle led to the failure and separation of the axle.