NTSB Factual Report

On October 6, 2015, about 1900 eastern daylight time, a Beech 58, N25734, sustained substantial damage when it impacted a fence while taxiing at Southwest Georgia Regional Airport (ABY), Albany, Georgia. The commercial pilot was not injured. Day visual meteorological conditions prevailed and no flight plan was filed for the local personal flight, which was conducted under the provisions of Title 14 Code of Federal Regulations Part 91. The flight originated from Dawson Municipal Airport (16J), Dawson, Georgia, around 1830.

According to the pilot, the flight was uneventful. Then, while taxiing from the runway, the pilot noted "softness" when he applied the left brake. Upon entering the ramp area, he applied the brakes and attempted to slow the airplane; however, the brakes had no effect. The airplane rolled into a grass area and impacted an airport perimeter fence.

According to Federal Aviation Administration records, the airplane, manufactured in 1973, was registered to a corporation in 2012. It was equipped with two Continental Motors IO-520 series, 285-hp engines. According to airplane maintenance logbooks, the most recent annual inspection was completed on March 9, 2015, and at that time, the airplane had accumulated 1,145.7 hours in-service. The maintenance log entry for the annual inspection stated that it was performed in accordance with the manufacturer guidance and the main landing gear brake linings were replaced. According to the manufacturer's guidance, item number 28 for the 100-hour inspection, stated "BRAKES – Check for condition and wear, ease of operation and proper release of the parking brake. Check for unusual brake chatter."

A postaccident examination of the airplane revealed substantial damage to the left wing. At the time of the accident, the Hobbs meter indicated 1214.8 hours. In addition, the brakes were examined and there was a trace amount of hydraulic fluid in both of the brake reservoirs. Hydraulic fluid was also noted on the surface of the left wheel torque plate. Furthermore, the left wheel torque plate assembly exhibited several fractures and the fitting tube was bent. The right wheel torque plate exhibited fractures as well, and one bolt was absent from the torque plate.

The main wheel torque plates and an attachment bolt from the right wheel plate were removed from the airplane and sent to the NTSB Materials laboratory for further examination. Both plates were fractured into multiple pieces and each plate contained several bolt holes, which were intersected by a fracture. Bench binocular microscope examination of each plate revealed crack arrest marks typical of fatigue cracking emanated from several bolt holes. Furthermore, the fatigue crack regions exhibited a black tint consistent with oxidation in ferrous metal. The fatigue crack terminated and regions outside the fatigue crack exhibited a rough granular texture consistent with overstress separation.

The attachment bolt from the right wheel plate was fractured on a slant plane and contained fracture features typical of overstress separation.

NTSB Probable Cause

The mechanic's inadequate inspection of the brake system during the most recent annual inspection, which resulted in the failure of both left and right main landing gear torque plates and a subsequent loss of braking action.