No fatalities

Pilot Reports Wheel Separation After Improper Maintenance

Big Bear City, CA, United States

On March 11, 2011, an AERONCA 7EC was involved in an aviation accident near Big Bear City, CA. No fatalities were reported. Investigators recorded the probable cause as: The pilot's failure to properly secure the wheel’s retaining nut with a cotter pin during maintenance. This summary draws on records from NTSB; 4 related events involving the same aircraft type or operator are linked below.

SourcesNTSBPrimary reportUpdated 2026-08-03Data APIEditorial standards

A pilot removed and reinstalled a landing gear wheel without properly securing the retaining nut, leading to wheel separation during takeoff roll and a subsequent landing incident with aircraft damage.

Incident Overview

A pilot reported that prior to a scheduled takeoff, he removed the left main landing gear wheel because its tire had a slow air leak. The pilot, who holds an airframe and powerplant mechanic certificate, indicated that after replacing the tube, he reinstalled the wheel on his airplane. During the maintenance, he did not properly secure the wheel’s retaining nut with a cotter pin.

Sequence of Events

During the subsequent takeoff roll, the attachment nut unscrewed, and the wheel separated from the axle and airplane. The pilot continued to fly around the area for about 30 minutes to burn off fuel. Upon landing, the airplane veered left off the runway and nosed over.

Damage Assessment

The accident resulted in damage to the aircraft structures, including broken wing ribs and a lift strut.

Probable Cause

The pilot's failure to properly secure the wheel’s retaining nut with a cotter pin during maintenance.

Contributing factors

PilotIncorrect service/maintenance

Frequently asked questions

What happened in the 11 Mar 2011 AERONCA 7EC accident near Big Bear City, CA?

A pilot removed and reinstalled a landing gear wheel without properly securing the retaining nut, leading to wheel separation during takeoff roll and a subsequent landing incident with aircraft damage.

Were there any fatalities in the 11 Mar 2011 AERONCA 7EC accident?

No fatalities were recorded in this accident.

What aircraft was involved and where did it happen?

The accident on 11 Mar 2011 involved an AERONCA 7EC, at Big Bear City, CA.

What was the probable cause of the accident?

The pilot's failure to properly secure the wheel’s retaining nut with a cotter pin during maintenance.