ATL96LA078

The pilot reported that loss of power occurred in both engines after he entered the traffic pattern for a full stop landing. The airplane collided with trees during an emergency landing in a cotton field near the airport. Subsequent review of the aircraft maintenance logs disclosed that Mitsubishi MU-2 Service Bulletin (SB) 130A had not been accomplished on this airplane. According to the manufacturer, an inadvertent failure or the improper installation of a filler cap after refueling may cause an air pressure differential between the center and outboard portions of the main integral fuel tank. Air leakage from the filler cap may result in failure of the fuel transfer system to move fuel from the outboard tank section to the center tank section. To eliminate this possible malfunction, the operator was to remove vent check valves from the bulkhead between the tanks in accordance with SB 130A. The operator's maintenance policies required that, company jet and turbo propeller aircraft be maintained under a maintenance program in accordance with FAR Parts 135.415, 135.417, 135.423, 135.443, and a corporate flight management approved aircraft inspection program (AAIP). The maintenance inspection program also included compliance with manufacturers' service bulletins and service letters.

On April 7, 1996, at 1155 central daylight time, a Mitsubishi MU-2B, N310MA, collided with a tree and the ground during an emergency landing near Panola County Airport, in Batesville, Mississippi. The personal flight operated under the provisions of Title 14 CFR Part 91, and the pilot had filed an instrument plan for this flight. Visual weather conditions prevailed at the time of the accident. The airplane sustained substantial damage, and the private pilot and passenger were not injured. The flight departed Montgomery, Alabama, at 1055 hours.

According to the pilot, both engines quit after he entered the traffic pattern for a full stop landing. The pilot confirmed that the fuel selectors were in the on position and feathered both propellers. He selected an open field, and made an emergency landing one mile south of the airport. The airplane collided with a tree during the emergency landing.

A review of the aircraft maintenance logs disclosed that Service Bulletin No. 130A had not been accomplished on this airplane. According to a manufacturer field report, an improperly installed filler cap after refueling, may cause an air pressure head between the center tank and outboard tanks. The air leakage from the filler cap resulted in a possible failure of the fuel transfer system to transfer fuel from the outboard tank to the center tank. To eliminate this possible malfunction, the operator is instructed to remove vent check valves from the bulkhead between the tanks.

A review of the company's maintenance policies, stated that the company jet and turbo propeller aircraft shall be maintained under a maintenance program in accordance with FAR Parts 135.415, 135.417, 135.423- 135.443, and corporate flight management approved aircraft inspection program (AAIP). The maintenance inspection program also included compliance with manufacturers service bulletins and service letters.

The wreckage examination revealed that enough fuel was in the fuel system to operate the engines. During the wreckage examination, the right engine assembly , still attached to the airframe, was started and ran for several minutes using fuel from the aircraft fuel supply (see attached inspector's report). Impact damage prevented the functional check of the left engine assembly. The visual and physical examination of the left engine assembly failed to disclose a mechanical problem.