History of Flight
On September 5, 2011, at approximately 1833 central daylight time, a Socata TBM 700, registration N850SY, impacted terrain near Mount Pleasant, Wisconsin, during a forced landing following a loss of engine power. The pilot sustained fatal injuries. The airplane was registered to Green Plane LLC and operated under 14 CFR Part 91 as a personal flight. Visual flight rules (VFR) conditions prevailed, and the flight operated on an instrument flight rules (IFR) flight plan. The flight originated from Central Wisconsin Airport (CWA) in Mosinee, Wisconsin, at about 1626, with an intended destination of Waukegan Regional Airport (UGN) in Waukegan, Illinois.
GPS track data from the Garmin G1000 avionics system indicated that after departing CWA, the airplane performed two full stop landings at CWA before proceeding toward UGN. At 1653, the airplane took off from runway 8 and flew southeast, climbing to about 19,000 feet mean sea level (msl) by 1703:15. Data showed that during the climb, the airplane was in coordinated flight, but after leveling off and accelerating, lateral acceleration increased to values exceeding 0.15 g with a left bank exceeding 5 degrees, indicating a slip condition that persisted for the remainder of the flight.
At 1811:30, the airplane began descending from 19,000 feet msl. At 1822:33, while at 11,000 feet msl and about 7 nautical miles north of Timmerman Airport (MWC), the avionics recorded a momentary complete loss of engine torque. The pilot informed the controller of a fuel pressure problem and chose to continue to UGN. At 1829:29, another complete loss of engine torque occurred. The pilot reported the power loss and attempted to glide to John H. Batten Airport (RAC) in Racine, Wisconsin. The airplane descended at about 100 knots indicated airspeed. The accident site and last recorded GPS position were about 3 miles southwest of the approach end of runway 4 at RAC.
Pilot Information
The pilot held a commercial pilot certificate with single-engine land and instrument airplane ratings and a third-class medical certificate issued on April 28, 2011, with a corrective lenses restriction. He had logged approximately 2,075 hours total flight time, including about 165 hours in the accident airplane. A flight review was completed on February 5, 2011. The pilot had received type-specific training from SimCom Training Centers in August 2010 and from Turbine Solutions, Inc. in February 2011. Training records from Turbine Solutions noted average knowledge of airplane systems and procedures, and the instructor discussed the possibility of stepping down to a less complex airplane or having another pilot accompany on long cross-country flights. The pilot completed recurrent training and received a completion certificate on February 5, 2011.
Aircraft Information
The accident airplane was a Socata TBM 700N, serial number 546, a single-engine low-wing monoplane with retractable tricycle landing gear and seating for six. It was powered by a Pratt & Whitney Canada PT6A-66D engine, serial number RV0210, rated at 850 shaft horsepower. The airframe and engine had accumulated 217.8 total hours at the time of the accident. The most recent annual inspection was on July 28, 2011, at 201.9 hours, and the most recent maintenance action on August 9, 2011, involved troubleshooting a flap problem.
Meteorological Information
Weather conditions at John H. Batten Airport (RAC) at 1853 included wind from 10 degrees at 11 knots gusting to 19 knots, visibility 10 miles, scattered clouds at 3,600 feet agl, temperature 14°C, dew point 7°C, and altimeter 30.15 inches of mercury.
Wreckage and Impact Information
The airplane came to rest on a flat farm field facing east. The initial impact point was about 130 feet south of the main wreckage, located on the north side of a road ditch. The fuselage was fractured near the aft edge of the entry door. Tail surfaces remained attached and undamaged. The elevator trim tabs were neutral, and the rudder trim tab was displaced left by about 10 mm. The forward fuselage was intact with lower crushing and skin buckling. The engine remained attached with firewall bending. Both wings remained partially attached, with leading edge crushing. The left flap was separated at about half span; the right flap remained attached. The propeller blades were not feathered; three blades exhibited rearward bending and chordwise abrasion, and the fourth showed twisting toward low pitch. An odor of aviation jet fuel was present.
Cockpit documentation found the power, propeller, and condition levers forward; fuel selector on left tank; landing gear up; auxiliary boost pump in auto; and fuel mode selector in manual. Postaccident examination revealed no anomalies in the fuel tanks or engine that would have prevented operation. The engine and accessories were functionally tested with no findings that would have prevented normal operation.
Medical and Pathological Information
An autopsy performed by the Waukesha County Medical Examiner's Office attributed the pilot's death to injuries received in the accident. Toxicology testing detected rosuvastatin in urine but not in blood, and theophylline in both blood and urine.
Additional Information
The airplane had integral fuel tanks in each wing, divided into inboard feeder and outboard storage areas. One-way valves allowed fuel to flow from storage to feeder but prevented reverse flow. The feeder section capacity was about 8.7 gallons. The flight data showed that the airplane was in a slip condition for about 19 minutes before the first power loss, with average lateral acceleration of 0.14 g and average left bank of 8 degrees. The fuel quantity indication was considered unreliable due to the lateral acceleration. The yaw damper system was designed to achieve coordinated flight and automatically actuate rudder trim, but its engagement status was not recorded. Functional testing of the rudder trim system and manual electric yaw trim revealed no anomalies. A test flight in an exemplar airplane with left rudder trim deflection reproduced similar lateral acceleration and bank angle values. The Pilot's Operating Handbook specified emergency procedures for engine failure and forced landing, including feathering the propeller and retracting landing gear for maximum glide range. The maximum range glide distance from the altitude of the final power loss (about 6,970 feet agl) was approximately 16 nautical miles, per the handbook's profile.