History of Flight
On July 25, 2015, at approximately 1040 eastern daylight time, a Beech A36, registration N6677D, was substantially damaged during an emergency landing following a partial loss of power during takeoff from Duchess County Airport (POU) in Poughkeepsie, New York. The private pilot and sole occupant except for a passenger received minor injuries; the passenger was not injured. Visual meteorological conditions existed, and an IFR flight plan had been filed for the flight to Burlington National Airport (BTV) in Burlington, Vermont, operating under 14 CFR Part 91.
The pilot reported that after arriving at POU from Lehigh Valley International Airport (ABE) in Allentown, Pennsylvania, he added 15 gallons of fuel and sumped the tanks. After starting the engine, he taxied, performed a runup, checked the magnetos, and cycled the propeller. During takeoff from runway 24, he noticed a vibration and unusual noise at rotation. Suspecting a wheel issue, he applied brakes and retracted the landing gear, but the vibration continued. The engine then partially lost power, and the airplane could not climb despite the propeller, throttle, and mixture being full forward. With low airspeed, the pilot determined he could not return to the airport. He maneuvered to clear power lines ahead, then pushed the nose down to avoid a stall and executed a gear-up landing approximately 300 feet beyond the wires.
Aircraft Information
The accident airplane was a low-wing, single-engine, retractable-gear aircraft of conventional metal construction. It was powered by an air-cooled, six-cylinder, horizontally opposed Continental IO-520-BB engine rated at 285 horsepower, driving a McCauley three-bladed constant-speed propeller. The airplane was manufactured in 1979. Its most recent annual inspection was completed on December 17, 2014, at which time the airframe had accumulated 6,796.6 total hours. The engine was a factory rebuilt unit installed on February 23, 2012, at a tachometer time of 6,103.9 hours. According to the pilot, the engine had accumulated 790 hours by the accident date.
Meteorological and Airport Information
The recorded weather at POU at 1047, about seven minutes after the accident, included calm winds, 10 miles visibility, clear skies, temperature 25°C, dew point 13°C, and an altimeter setting of 30.01 inches of mercury. No other airport information was provided.
Wreckage and Impact Examination
Examination of the accident site showed that the airplane initially contacted the ground belly-first in a grassy area, then traveled over a large rock and came to rest. The landing gear was in the up (stowed) position. All major components were present, and substantial damage occurred when the airplane struck and traversed the rock. The outboard sections of all three propeller blades were bent backward. The right-side nose wheel door separated at the hinge line, the lower cowling was buckled and crushed aft, and the upper cowling partially opened on impact. The nose landing gear wheel well was crushed upward, and both right-side engine mounts were fractured. The throttle body had one mount lug fractured, and two fuel fittings were fractured. The lower portion of the firewall was buckled, and the fuselage buckled just aft of the firewall. Wing flaps were at 15°, and the inboard left flap was bent. Fuel was visible in both wing tanks.
Maintenance History
Review of maintenance records revealed that on June 14, 2013, about 279 hours after engine installation, the auxiliary fuel pump was replaced. On February 6, 2014, maintenance personnel bled the fuel line, checked the fuel strainer, and cleaned the injectors due to a rough-running engine; the engine was test-run and returned to service. The following day, spark plugs were cleaned, gapped, and rotated, and fuel injectors were cleaned and reinstalled; no discrepancies were noted. The annual inspection on December 17, 2014, and subsequent spark plug service the next day showed no anomalies. On May 11, 2015, an oil and filter change was performed.
Engine Test and Fuel System Examination
On November 2, 2015, an engine test run was conducted to investigate the reported rough running and power loss. Prior to the test, several damaged or removed items were replaced with substitute parts. Magneto timing was checked: left magneto at 21° BTDC, right at 20° BTDC (specified 22° BTDC). The engine started normally and operated through various RPM steps without hesitation or interruption. A cylinder leakage test after the run showed varied results across cylinders (e.g., No. 1 at 17/80 PSI, No. 4 at 36/80 PSI).
The airplane's low-wing configuration required fuel pumps; the system included an engine-driven pump and an electric auxiliary fuel pump. The auxiliary pump had not been disassembled since manufacture. On May 4, 2016, the pump was tested and produced 53 gph at 16 psi with a 2.1-amp draw (specifications: minimum 42 gph at 16 psi, max 3 amps), indicating normal operation. However, a leak was discovered at the discharge fitting. Disassembly revealed deep scratches on the O-ring boss of the pump-side fitting and a piece of metal embedded in the O-ring. After replacing the fittings, no leaks were found during retesting.
No probable cause was stated in the source.