NTSB Factual Report

HISTORY OF FLIGHT

On November 10, 2014, about 1258 eastern standard time, a Mooney M20C, N6581U, was substantially damaged when it impacted a fence and terrain shortly after takeoff from Greenbrier Valley Airport (LWB), Lewisburg, West Virginia. The private pilot received serious injuries. Day visual meteorological conditions prevailed and no flight plan was filed for the flight, which was destined for Hanover County Municipal Airport (OFP), Richmond, Virginia. The ferry flight was conducted under the provisions of Title 14 Code of Federal Regulations Part 91.

According to a witness who was working at the airport, the pilot taxied to the beginning of runway 04, paused for a brief period, and then began the takeoff roll. The airplane lifted off within the first 2,000 feet of the 7,003-foot-long runway. The takeoff roll and initial climb appeared normal, and the engine sounded "typical." At about 200 feet above ground level the airplane leveled off, and continued down the runway centerline. He observed that the landing gear remained down, and the flaps remained partially deployed. The airplane entered a slight left banking turn, which quickly increased to a "very sharp" left bank, and the nose "dropped." He observed the airplane return to a level attitude as it descended out of view.

A second witness stated that as the airplane began its steep left bank, the wings were "straight up and down" with the left wing pointed toward the ground. He stated at that point, "it didn't sound like he had any power", and before it went out of his view, the engine "appeared to rev to full power". A third witness located in a parking lot near the departure end of the runway saw the airplane as it was flying toward the northwest, perpendicular to the runway. She stated that it was "wig-wagging," which she further described as rolling from left to right at a relatively steep angle "considerably greater than normal takeoffs" she had seen. She stated that the airplane then levelled its bank angle, but then pitched up and shortly thereafter the "nose came down."

The pilot stated that he could not recall the sequence of events following the airplane's takeoff and initial climb.

PERSONNEL INFORMATION

According to Federal Aviation Administration (FAA) records, the pilot held a private pilot certificate issued January 13, 2007, with ratings for airplane single-engine land, multiengine land, and instrument airplane. His most recent third-class medical certificate was issued on April 18, 2013, with a restriction of "must wear corrective lenses."

The pilot reported a total of 3,500 flight hours of experience, of which 900 were in the accident airplane make and model.

AIRCRAFT INFORMATION

The four-seat, low wing, retractable gear airplane was manufactured in 1962. It was powered by a Lycoming O-360-A1A 180-hp reciprocating engine, equipped with a Hartzell two-blade, constant speed aluminum propeller.

The date of the airplane's most recent annual inspection could not be determined. The pilot/owner reported that the airplane had been recently repossessed from the previous owner, and he had purchased it the month prior to the accident without any associated maintenance records. He had applied for and received a special flight (ferry) permit from the FAA to return the airplane to his home airport. The ferry permit required that an inspection be performed prior to the flight by an appropriately-certified mechanic or repair station, to determine if the aircraft was safe for flight. The pilot indicated that this inspection was not performed, and no records of such an inspection were found during the investigation.

METEOROLOGICAL INFORMATION

The 1315 recorded weather observation at LWB included: calm wind, 10 miles visibility, clear skies, temperature 16 degrees C, dew point 2 degrees C; barometric altimeter 30.07 inches of mercury.

WRECKAGE AND IMPACT INFORMATION

The airplane impacted a fence and terrain in a pasture about 1/4 mile to the left of the runway 04 centerline, about 1,000 feet prior to the departure end of the runway. The debris path began at the initial impact point, which was identified as a broken fence post, and extended about 50 yards on a 323-degree magnetic heading to the main wreckage. There was no evidence of pre or post impact fire. All major components of the airplane were co-located with the main wreckage, with the exception of the left main landing gear, located about 15 feet from the initial impact point, and the propeller/hub assembly, which was located about 10 feet to the southwest of the main wreckage.

The left wing sustained leading edge impact damage and the left flap was separated from its outboard 3 attachment points. A section of the right wing was bent downward about 5 feet from the wing tip. The empennage was mostly undamaged except for the left horizontal stabilizer, which sustained leading edge impact damage. Flight control continuity was confirmed from the cockpit controls to all control surfaces, with the exception of the left flap, which was impact damaged. Additionally, the left seat rudder pedals were impinged by damaged structure. The right wing fuel tank contained fuel consistent with the color and odor of 100LL aviation fuel; the left wing tank was breached and was devoid of fuel. First responders estimated that about 20 gallons of fuel had leaked onto the ground under the left wing. When electrical power was applied to the airplane, the right fuel gauge indicated about ¾ full, the left gauge indicated about ¼ full.

The cockpit exhibited impact and crush damage. The seats remained attached to the seat rails, the left seatbelt was found intact and unbuckled. The fuel selector valve was found in the "LEFT" tank position. The elevator trim indication could not be determined due to impact damage. The cockpit engine controls were found with the throttle slightly inward from idle position, and the shaft was bent downward about 45 degrees. The mixture control was found about one-half inch out from the full rich (in) position. The propeller control was found in the full forward position. The flap handle was in the "UP" position and the indicator position could not be determined due to damage. The landing gear handle grip was separated from the bar, and the bar was found in the landing gear up position. Battery power was applied to the airplane and the operation of the stall warning system was confirmed.

The engine remained secure to its mounts, which were attached at all four corners of the firewall. The propeller was impact-separated from the crankshaft flange. One propeller blade displayed an impact mark on the leading edge approximately 2 inches from the tip, exhibited chordwise scratching, and was bent aft approximately 14 inches from the tip. The other blade had one leading edge nick approximately 1 inch from the blade tip; no chordwise scratching was present. Engine mechanical continuity, valve action, and thumb compression on all cylinders were confirmed by hand rotation of the engine at the propeller flange. A borescope examination of each cylinder revealed that the #4 intake valve showed signs of erosion on the valve seat, all cylinder walls and piston tops were unremarkable.

The engine-to-magneto timing was measured and found to be approximately 48 degrees before top dead center. The manufacturer's specification was 25 degrees. Both magnetos produced spark through all the ignition leads when turned by an electric hand drill.

The carburetor was impact separated and exhibited soot deposits in its throat. No other anomalies were noted with the fuel system components, and fuel present in the carburetor bowl tested negative for the presence water.

NTSB Probable Cause

The pilot's failure to maintain airspeed while maneuvering, which resulted in the airplane exceeding its critical angleofattack and experiencing an aerodynamic stall. Contributing to the accident were abnormal engine operation due to improper magneto-to-engine ignition timing and the pilot's failure to have the airplane inspected before the flight as required by the special flight permit.