CEN15FA214

The impact with power lines for reasons that could not be determined based on the available information.

Shortly after the private pilot and flight instructor took off on a local training flight several witnesses reported seeing the airplane's wings rocking back and forth just before the airplane struck power lines and then terrain. None of these witnesses reported hearing a loss of engine power. Neither of the pilots recalled the events leading up to the accident or the accident itself. Witness marks on the airplane and propeller were consistent with an impact with power lines. Signatures on the propeller were consistent with little to no engine power at the time of the impact with the power lines; however, investigators were unable to determine if the pilot reduced engine power, or if the engine lost power, before impact. An examination of the airframe and engine revealed no preimpact anomalies that would have precluded normal operation. The airplane was determined to be 100 lbs over gross weight (about 2,751 lbs) at the time of takeoff. Calculations using the airplane's performance charts and the weather conditions that existed at the time of the accident indicated that the airplane had sufficient runway available to clear a 50-ft obstacle at a gross weight of 2,600 pounds. It is unknown how significantly the airplane's overweight condition would have impacted the airplane's climb performance.

The accident airplane was equipped with an Electronics International MUX-8A (serial number 079179). The unit was not damaged and the non-volatile flash memory was extracted normally, at the National Transportation Safety Board Vehicle Recorders Laboratory, following the manufacturer's procedures. The data extracted spanned from November 23, 2005, through May 2, 2015. Data consistent with the accident flight were sampled once every six minutes and included two sets of data. The first set of data was recorded at 0957 and provided the following readings: EGT1 - 950 EGT2 - 977 EGT3 – 927 EGT4 – 1015 EGT5 – 1000 EGT6 - 967 CHT1 - 236 CHT2 - 237 CHT3 – 246 CHT4 - 242 CHT5 – 234 CHT6 - 219 The second set of data was recorded at 1003 and provided the following readings: EGT1 - 1073 EGT2 - 1152 EGT3 – 1032 EGT4 – 1130 EGT5 – 1112 EGT6 - 1065 CHT1 - 333 CHT2 - 335 CHT3 – 347 CHT4 - 332 CHT5 – 307 CHT6 – 323 According to Continental Motors, the exhaust gas temperature (EGT) numbers did not approach typical full power temperatures. KORG is a public uncontrolled airport located 3 miles southwest of Orange, Texas, at a surveyed elevation of 13.2 feet. The airport had 2 open runways, runway 4/22 (5,500 feet by 75 feet, asphalt), and runway 13/31 (3,000 feet by 50 feet, turf). The engine was relocated to Mobile, Alabama, for further examination. The accessory case, alternator, engine mount, and carburetor were impact damaged. The mounting point on the accessory case for the starter was repaired and an exemplar carburetor was mounted for engine run purposes only. The engine was fitted with exhaust tubing, thermo couplings, pressure lines, and test pads for test purposes only, and was relocated to the engine test cell. The engine was mounted to the test cell for operation and a test club propeller for the engine was attached at the propeller flange. A pre-engine run compression test was performed with the following results: Cylinder 1 – 2, cylinder 2 – 7, cylinder 3 – 63, cylinder 4 – 10, cylinder 5 – 22, and cylinder 6 – 7. Master orifice level prior to the test was 39. The engine started and ran through a series of rpm increases for 20 minutes without any hesitation, stumbling, or interruption in power. Cylinder temperature, manifold pressure, oil temperature, oil pressure, fuel pressure, and fuel temperature were monitored and recorded at varying engine rpms. A post-engine run compression test was performed with the following results: Cylinder 1 – 60, cylinder 2 – 40 (exhaust), cylinder 3 –75, cylinder 4 – 40 (exhaust), cylinder 5 – 52 (exhaust), and cylinder 6 – 40 (exhaust). The carburetor was impact damaged and could not be functionally tested. The mixture arm was bent, and the casing for fuel metering valve and case for the throttle valve were impact damaged. The fuel screen was free of visible contamination. The carburetor was disassembled – no anomalies were noted that would have precluded normal operation. Weight and Balance According to the most recent weight and balance, dated November 23, 2005, the basic empty weight of the airplane (including engine oil) was 1,835.7 pounds. According to the FAA Type Certificate Data Sheet, the airplane's maximum weight was 2,650 pounds. Fuel receipts and entries in the pilot's logbook indicated the last flight was on April 19, 2015, and the airplane was serviced with 12 gallons of fuel on April 25, 2015. It was reported that the two main fuel tanks and auxiliary fuel tank were full (39.5 gallons of fuel recovered). The useful fuel weight was 252 pounds. The combined weight of the pilot and flight instructor was 564 pounds (based upon their weights reported during medical certificate application). The weight of the gym weights and cooler of ice was 99.4 pounds. The estimated weight of the airplane at takeoff was at least 2,751.1 pounds. According to a weight and balance calculation document found in the wreckage, the empty weight of the airplane was 1,670 pounds, the weight of the occupants was estimated at 520 pounds, baggage and cargo was estimated at 200 pounds, and 10 pounds of fuel was deducted for engine start, taxi, and takeoff allowances. The total fuel weight was 264 pounds and the sub total takeoff weight was calculated at 2,644 pounds. Takeoff Performance According to the takeoff distance chart located in the Beechcraft B-35 pilot operating handbook, performance section, the airplane should have required between 700 (no obstacle) and 1,300 feet (50-foot obstacle). The conditions for this performance include takeoff power, flaps up, landing gear retracted, and mixture leaned to maximum rpm at full throttle. A temperature of 25 degrees C, a weight of 2,600 pounds, and a headwind of 3 knots were also factored. The accident site was located in level terrain vegetated with grass. The accident site was at an elevation of 16 feet msl and the airplane impacted on a magnetic heading of 040 degrees. The main wreckage included the right wing, the left-wing, the fuselage, and the engine and propeller assembly. Both wings remained attached to the fuselage. The engine partially separated at both upper engine mounts. The cabin of the airplane was impact damaged and the occupiable space of the cabin was not compromised or reduced except for at the floorboard rudder pedals. The forward wind screen was broken on the left side and was impact damaged. The throw over single control yoke was impact damage and separated. The damage was consistent with the yoke being on the pilot's side at the time of impact and separation. The instrument panel was impact damaged. The turn coordinator glass was impact damaged. The magneto key was found in the "both" position. The throttle control was about 1 inch out. The propeller control was impact damaged and the mixture control was full rich. The leading edge of the right wing was crushed, torn, and wrinkled. A 4-foot section of the leading edge of the wing about mid span was torn and separated. The right aileron separated at the outboard hinge and was bent and wrinkled. The inboard trailing edge of the right flap was bent up. The right main landing gear was retracted and secured within the wheel well. Control continuity for the aileron was confirmed from the flight control inboard to the control yoke. The outboard bottom portion of the right wing contained witness marks consistent with a wire strike. The left-wing was bent up and diagonally wrinkled about mid span. The skin along the leading edge was crushed and wrinkled. The inboard trailing edge of the flap was torn. The left aileron remained attached and was wrinkled. Control continuity for the aileron was confirmed from the flight control inboard to the control yoke. Discoloration on the leading edge of the left wing was consistent with arcing. The empennage was partially separated from the airframe. A small section was cut for recovery purposes. The emergency locator transmitter was in the "On" position and was shut off by the airport manager following the accident. The elevator/rudder control continuity was confirmed from the separation point aft to the control surfaces. The separation points on all but one of the control cables were consistent with overload and impact damage. One cable was cut during the recovery process. The upper and lower skin on the left elevator/rudder was wrinkled. The flight control was unremarkable. The right elevator/rudder was unremarkable. The skin on the fuselage from the separation point to the empennage was wrinkled on both sides. The propeller assembly remained attached to the engine at the propeller flange. The upper and lower cowling and firewall were wrinkled and torn. One lead on the right magneto harness was impact damaged. Fuel was observed in the lines up to the fuel pump. The upper bank of spark plugs were removed and appeared new. No external catastrophic damage was observed on the en