NTSB Factual Report

HISTORY OF FLIGHT

On January 29, 2006, at 1445 central standard time, a Cessna T210M, N761ZV, registered to and operated by a individual as a 14 CFR Part 91 personal flight, collided with the ground during a precautionary landing at Murfreesboro Municipal Airport (MBT), Murfreesboro, Tennessee. Visual meteorological conditions prevailed at the time of the accident, and a flight plan was not filed. The airplane was destroyed by post-crash fire, and the private-rated pilot sustained serious injuries, and later died on March 7, 2006, as a result of those injuries. The flight originated from the Smyrna Airport, Smyrna, Tennessee, on January 29, 2006, at 1436.

According to the air traffic controller at Smyrna/ Rutherford County Airport, the pilot took off from runway 19 at 1436. According to the controller, at 1445 the pilot radioed the tower and reported, "He was having problems with the trim, and was going to return to the airport". The pilot also reported "that he had to apply allot of back pressure on the yoke, and the electric trims were not working". The controller requested a position report, and the pilot advised him that he was south of the MBT. The pilot asked what runways were available at MBT, and the controller told him "18-36". The pilot replied, "Yeah I'm going for that". No further radio transmissions were received from the pilot.

Witnesses on the ground near MBT reported seeing the airplane flying "erratic", and "porpoising". The airplane collided with the ground short of runway 18 at MBT. The emergency personnel who arrived on scene reported that the pilot stated, "that the electric trim was not working, and he was fighting the yoke all the way down".

PILOT INFORMATION

Review of information of file with FAA Airman's Certification Division, Oklahoma City, Oklahoma, revealed the pilot was issued a private pilot certificate on January 21, 2005, with ratings for airplane single-engine land and instrument airplane. The pilot's last flight review was conducted on July 13, 2004. The pilot holds a third-class medical certificate issued on April 28, 2004, with the restriction, "must wear corrective lenses." The FAA airman's report revealed that the pilot had a total of 1,000 civil hours. The pilot's logbooks were not recovered for review.

AIRCRAFT INFORMATION

The airplane was a 1978 Cessna T210M (serial number 21062657). It was a six-seat, high-wing airplane of predominantly aluminum construction with fixed tricycle landing gear. A 300-horsepower Continental TSIO-520 engine (serial number 293875) powered the airplane. Review of delivery documents revealed that the airplane was first delivered on May 25, 1979. The current owner, the pilot, purchased the airplane on October 16, 2002.

Review of the maintenance records from the Smyrna Air Center revealed that the last annual inspection was conducted on January 13, 2006. The tachometer time at annual inspection was 2698.2 hours. The aircraft logbooks were not recovered for review. The current tachometer time could not be determined due to the fire damage.

METEOROLOGICAL INFORMATION

The weather reporting facility at KMBT reported at 1519, winds were from 220 degrees at 12 knots, greater than 10 miles visibility, sky few at 6000, altimeter-setting 29.79.

WRECKAGE EXAMINATION

Examination of the wreckage debris path by an FAA inspector revealed that the airplane collided with the ground approximately 300 yards short of runway 18 at MBT. The airplane travel approximately 156 yards from the initial ground scar to the final resting place. A post-crash fire consumed the cockpit area aft of the firewall, cabin, and inboard portion of the left wing. The tailcone and all the aerodynamic surfaces of the empennage were also consumed by post-crash fire. Flight control cable continuity was confirmed for the primary and secondary flight control surfaces. The empennage flight control cables were separated in two places, at the forward cockpit pedestal and just forward of the empennage.

Examination of the propeller revealed the spinner and hub were impact-damaged. All three blades were bent aft and showed chord-wise and span-wise scratches throughout.

Examination of the engine assembly revealed it separated from the main wreckage with heat damage to the baffling, accessory section, and both left and right sides of the engine. The engine mounts were separated from the firewall, and the cowling was heat-damaged. The cowling was removed, and the accessories were intact with the exception of the induction and exhaust system. Examination of the exhaust system revealed it had impact damage. The induction assembly revealed fire and impact damage. The turbocharger had sooting to its housing and the turbine could be rotated freely by hand. Dirt and debris were found in the turbine area. The turbocharger waste-gate was found in the full open position with heat damage. The ignition harness had fire damage. The left and right magnetos were intact and turned freely. When turned, the impulse coupling engaged, and spark was observed at the ignition leads. The upper and lower spark plugs were removed and the electrodes exhibited normal wear and deposit when compared to the Champion Check-A-Plug comparison chart. The fuel pump was removed from the engine and turned freely by hand. The fuel pump drive was intact and undamaged. The fuel manifold valve was removed and a small amount of fuel was found in the fuel manifold cavity. The engine cylinders were examined using a boroscope in accordance with TCM SB03-3 revealing that the piston heads, combustion chambers, and cylinder bores showed no anomalies. The crankshaft was rotated, and valve train continuity was established.

Examination of the elevator trim actuator and electrical trim revealed they were heavily damaged by post-impact fire. The elevator trim tab actuator measurement was 2.1 inches (approximately 20-degrees tab-up/aircraft nose down). The trim chains at the cockpit pedestal and elevator tab assembly were on their sprockets and intact. Rotation of the actuator double sprocket in a counter-clockwise direction caused the screw to extend aft, which corresponds to the tab-up position. The elevator trim actuator screw moved freely, and no mechanical damage was found.

Examination of the electric trim drive assembly sprocket revealed it moved freely and was held in place by a safety-wired bolt. The electric trim drive assembly was coupled to the sprocket through a stub shaft and a hexagonal socket. The outer cover of the electric trim drive assembly was removed and all gears rotated freely. The solenoid activated a lever arm, which engaged the electric motor, and the lever arm was also able to move without binding or jamming. The electric motor gears were in the disengaged position. The internal components of the electric trim drive assembly were heat damaged.

PATHOLOGICAL INFORMATION

The private pilot died on March 7, 2006, as a result of thermal injuries received in the accident.

ADDITIONAL INFORMATION

The electric trim control assembly was sent to Sigma Tek for further examination with FAA oversight. Examination of the trim actuator mount, part number 44575-2201, was visually inspected, showed signs of excessive heat, and the data plate was missing. The safety wire securing the adjustment bolt was in place. The top spring washer was cracked. The whole output shaft/ clutch rotated freely in the mount bearing pair. An attempt was made to check the nominal clutch setting of 22 +/-3 in.lbs, by securing the output shaft and using a 75 in.lbs torque-wrench and tool sprocket assembly. The sprocket did not move when + / - 75 in.lbs was applied. The safety wire was removed and the clutch was disassembled. The top and bottom spring washers were each cracked through in one place. The sprocket still did not rotate relative to the output shaft. The thrust hub, clutch disc, sprocket, second clutch disc, and clutch hub was "fused" together. It was not possible to determine if the clutch was working at the time of the accident due to the heat damage caused by fire.

Examination of the trim actuator, part number 44430-2825, revealed there were numerous dents in the case, and the data plate was missing. The case was removed to determine the position of the relay contacts. The relay clear plastic covering was heat distorted, but was not internally damaged. The unit was disassembled, and continuity was checked with an ohmmeter. The relay was found to be in the un-energized state, which relates electrically to being in the position that would allow the pilot to control the trim with the switch on the control yoke. This position is the normal un-powered state of the relay. It was not possible to determine if the autopilot system or the pilot was in command of the electric trim system at the time of the accident. No determination could be made with respect to the position of the relay contacts at the time of the accident.

The wreckage of the airplane was released to Global Aerospace Incorporated c/o Leading Edge Investigations after the field and post accident examinations on December 6, 2006.

NTSB Probable Cause

The pilot's failure to maintain airplane control during a precautionary landing following a reported failure (undetermined) of the elevator trim control system.