Accident Overview
On May 13, 2012, at 1903 eastern daylight time, a Maule M-7-420AC (registration N420RP) attempted a forced landing on Pine Hill Lake in Hanover Township, Michigan, after the engine lost power. During the emergency descent, the airplane clipped a tree and impacted the water. Both occupants—the pilot and a passenger—exited the airplane and swam to shore. Neither was injured. The airplane sustained substantial damage.
Flight Details
The airplane was registered to and operated by Bull Dog Aviation of Alpena, Michigan, under 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed, 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) in Jackson, Michigan, for fuel.
According to the pilot's account to a Federal Aviation Administration (FAA) inspector, he had landed at Round Lake earlier to visit a relative. After departing, he circled back over the lake, saw Farwell Lake, and decided to land there. He performed a clearing pass and then made climbing left turns to enter the downwind leg, at which point the engine lost power. The pilot reported he did not have time to attempt an engine restart. Pine Hill Lake came into view, and during the descent, the airplane struck trees near the shore. The pilot then returned to the airplane and turned off the fuel selector.
Post-Accident Examination
After recovery, an FAA inspector drained only two gallons of fuel from the left tank. The right wing had struck a tree, rupturing the fuel tank, and examination of the tree showed signatures consistent with a fuel spray. The Maule M-7-420AC has interconnected inboard and outboard tanks in each wing, with a fuel control valve selecting left tank, right tank, or ON/OFF positions. The inspector found the fuel selector in the OFF position.
Examination of the turbine engine did not reveal why it lost power. Both the N1 and N2 shafts rotated freely, with continuity between the compressor and gas producer, and between the power turbine and accessory gearbox. The chip plugs were clean.
Component Testing
Various fuel components were removed and tested under FAA oversight. The engine fuel pump (part number 6899253, serial number 3483) was tested at Eaton Corporation in Cleveland, Ohio, on July 23. A Rolls Royce technical representative noted only residual fuel was present, less than expected. The unit tested satisfactory to factory specifications.
The main fuel control (part number 23057346, serial number 334664) was tested at Honeywell Engine Control Systems in South Bend, Indiana, on July 24. Again, only residual fuel was found, less than expected, and it tested satisfactory.
The propeller governor (part number 6875708, serial number 1705058A/B) and overspeed governor (part number 23032241C, serial number 2164897) were tested at Woodward on July 25, with a Rolls Royce representative present. Both units tested satisfactory.
Additionally, the FAA later applied electrical power to the Welden fuel pump, and it operated normally.