NTSB Factual Report

On May 13, 2012, at 1903 eastern daylight time, the pilot of a Maule M-7-420AC, N420RP, attempted to make a forced landing on Pine Hill Lake, Hanover Township, Michigan, after the engine lost power. During the emergency descent, the airplane clipped a tree and impacted the water. The pilot and his passenger, who were not injured, exited the airplane and swam to shore. The airplane was substantially damaged. The airplane was registered to and operated by Bull Dog Aviation, Alpena, Michigan, under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed at the time of the accident, and no flight plan had been filed. The flight originated at 1859 from nearby Round Lake and was en route to Jackson County Regional Airport (KJXN), Jackson, Michigan.

The pilot told a Federal Aviation Administration (FAA) inspector that he had landed at Round Lake earlier in the day to visit a relative. He departed Round Lake and was en route to KJXN for fuel. According to the pilot’s accident report, he took off to the south, circled, and flew back over the lake. He saw nearby Farwell Lake and decided to land there. He checked the area for traffic and made a clearing pass over the lake to notify traffic of his intention to land. He then made climbing left turns and was established on the downwind leg when the engine lost power. The pilot said he did not have time to attempt an engine restart. Pine Hill Lake came into view and during the descent towards that lake the airplane struck trees next to the shore. The pilot then returned to the airplane and turned off the fuel selector.

After the airplane was recovered from the lake, the inspector was only able to drain two gallons of fuel from the left tank. The right wing had struck a tree, rupturing the fuel tank. Examination of the tree revealed signatures consistent with a fuel spray. The Maule M-7-420AC has interconnected inboard and outboard tanks in each wing. The fuel control valve selects the left tank, right tank, and the ON and OFF positions. The FAA inspector found the fuel selector in the OFF position. Examination of the turbine engine failed to reveal why it lost power. Both the N1 and N2 shafts rotated freely with continuity between the compressor and the gas producer, and between the power turbine and the accessory gearbox. The chip plugs were clean.

Various fuel components were removed for testing. The engine fuel pump (p.n. 6899253, s.n. 3483) was tested at the Eaton Corporation, Cleveland, Ohio, on July 23, under the auspices of FAA. Also in attendance was a technical representative from Rolls Royce. The fuel pump was opened and only residual fuel was noted. The Rolls Royce representative said it was less than what was to be expected or was normally found. The unit tested satisfactory in accordance with factory specifications.

The main fuel control (p.n. 23057346, s.n. 334664) was tested at Honeywell Engine Control Systems, South Bend, Indiana, on July 24, under the auspices of FAA. A technical representative from Rolls Royce was also in attendance. Again, only residual fuel was found in the control, and the Rolls Royce representative again noted the amount was less than what was expected or normally found. It also tested satisfactory in accordance with factory specifications.

The propeller governor (p.n. 6875708, s.n. 1705058A/B) and overspeed governor (p.n. 23032241C, s.n. 2164897) were tested at Woodward on July 25, under the auspices of FAA. A technical representative from Rolls Royce was in attendance. The units tested satisfactory in accordance with factory specifications.

FAA later applied electrical power to the Welden fuel pump. The FAA inspector said it operated normally.

NTSB Probable Cause

A total loss of engine power for reasons that could not be determined during an exhaustive postaccident examination of the engine and its components.