ERA10FA024

Flight into terrain for undetermined reasons.

During an early morning departure, prior to sunrise, the aircraft impacted trees and terrain immediately after takeoff. Witnesses reported the sound of the engines were loud, although they did not observe the airplane take off. A postaccident examination of the airplane and engines revealed no mechanical discrepancies that would have precluded normal operation. The damage to both propeller assemblies was consistent with impact and fire damage. Although the forward baggage door had a gouge mark, it was not consistent with a baggage door coming in contact with a propeller blade in flight. The circumstances of the accident are potentially consistent with an incapacitating event involving this pilot, particularly, given evidence of coronary artery disease during the postmortem examination, or with spatial disorientation given the circumstances of the flight. The pilot was taking off during dark lighting conditions, over a dark unpopulated area. The absence of external visual cues and the accelerations associated with the takeoff and initial climb could have led to erroneous sensations of the airplane’s attitude which, if not effectively managed by the pilot, could explain the circumstances of the accident. There is insufficient evidence, however, to allow a conclusive determination as to which scenario, if either, actually occurred.

HISTORY OF FLIGHT On October 21, 2009, about 0624 eastern daylight time, a Piper PA-23-250, N62635, was substantially damaged when it impacted trees and terrain immediately after takeoff from the Summerville Airport (DYB), Summerville, South Carolina. Night visual meteorological conditions prevailed, and an instrument flight rules flight plan was filed with a destination of St. Lucie County International Airport (FPR), Ft. Pierce, Florida. The certificated commercial pilot/owner and the three passengers were fatally injured. The personal flight was conducted under the provisions of 14 Code of Federal Regulations Part 91. The airplane was based at DYB. A few days prior to the accident, the pilot was observed flying the accident airplane in the traffic pattern at night, and several individuals at the airport reported that the pilot did this to ensure that he was current for night operations. Email printouts that were found on the floor of the hangar where the accident airplane was stored contained communications between the four occupants about the weight and balance of the airplane. Their email discussions also included the decision to create a list of what items should be left behind if the original planned load exceeded the airplane limitations. Other paperwork found in the hangar documented the weights, in pounds and ounces, of the planned cargo items. The occupants of the airplane were headed to an amateur radio operator contest in the Bahamas. A flight plan was filed for a 0545 departure from DYB. Several individuals who lived in houses located southeast and northwest of the airport heard the accident airplane. One witness heard the engines of the airplane start up, and observed the airplane during its takeoff roll from runway 24. However, due to the location of the trees on his property, the witness was unable to see the airplane during the initial climb phase. Another witness reported that around 0615 she heard the airplane when it was "in the place where the airplanes sit before they take off," and that the engine sounds changed pitch twice. Most witnesses reported noticing that the sound of the engines was "loud." A witness reported that the runway lights were not illuminated prior to the accident. Several witnesses reported three or four post-accident explosions. Post accident activation by both the airport manager and the arriving medical helicopter revealed that all the lights illuminated correctly. About 0627, a Dorchester County Sheriff's patrol unit arrived on scene, and very shortly thereafter, the fire department units also arrived. PERSONNEL INFORMATION The pilot, age 69, held a commercial pilot certificate, with ratings for single-engine land, multiengine land, and instrument airplane. His most recent Federal Aviation Administration (FAA) second-class medical was issued on June 10, 2009. At that time, the pilot reported a total flight time of 4,326 hours of flight experience. According to documentation provided by a local certificated flight instructor, the pilot had accomplished a biennial flight review on January 29, 2008. AIRCRAFT INFORMATION The airplane was issued an FAA airworthiness certificate on April 15, 1976, and was registered to the accident pilot on May 16, 1997. It was equipped with two Lycoming IO-540-C4B5 engines. According to one maintenance provider familiar with the accident airplane, at the time of its most recent annual inspection, the hour-recording meter registered 2,260.1 hours, and there were 5,015.1 total hours of service on the airframe. On October 19, 2009 the oil was changed in both engines, and at that time, the hour-meter registered 2,345.4 hours, the left engine had accumulated 1,581.0 total hours in service, and the right engine had accumulated 1,906.4 total hours in service. METEOROLOGICAL INFORMATION The 0615 recorded weather observation at DYB included calm winds; visibility 10 miles, clear skies, temperature 4 degrees C, dew point 3 degrees C; altimeter 30.26 inches of mercury. AIRPORT INFORMATION The airport was equipped with a single runway oriented northeast to southwest and designated 6/24. The runway was 3700-feet-long and 75-feet-wide, constructed of asphalt, and was equipped with medium intensity runway lights that were pilot activated utilizing the common traffic advisory frequency (CTAF). The airport did not have an air traffic control tower. The runway lights are set to a timer and automatically turn off as programmed. A post-accident functional test of the airport runway lighting system revealed that all systems operated normally. Communication made over the CTAF and activation of the pilot-controlled lighting did not have recording capabilities and was not recorded. WERECKAGE AND IMPACT INFORMATION An on-scene investigation revealed that the airplane impacted the ground in a wooded area 584 feet south of the runway centerline, and approximately 2/3 of the way down runway 24. The first tree that the airplane impacted was 74 feet beyond the boundary of the wooded area. The surrounding trees were approximately 80 feet high. The tree and ground scars indicated a left-wing low attitude as the airplane entered the trees and it came to rest 93 feet from the point of first tree strike. The debris path was oriented on a 102 degree heading, and the wreckage was oriented on a 360 degree heading. The left wing outboard fuel tank was located along the debris path, 45 feet from the initial tree impact. It exhibited extensive impact damage, and was devoid of fuel. The remainder of the airplane exhibited fire and crush damage. The forward cargo compartment baggage door exhibited a gouge forward of the door locking handle and approximately 15 inches forward of the trailing edge and exhibited no thermal damage. The baggage door was found approximately 13 feet forward of the aircraft wreckage and the lock was void of a key. The instrument panel and instruments were destroyed by post impact fire. The two front seat and center seats were separated from their tracks and exhibited impact damage and post impact fire damage. The main cabin door was separated and exhibited impact damage and post impact fire damage; however, it was in the locked position. Several restraint system buckles were located and found to be latched; however, all were void of webbing due to the post impact fire. The main spar, aft spar, and cabin tubular frame were fractured with molten metal present from the post impact fire. Control cable continuity for the ailerons and elevator, from the cockpit floor area where the control column was located, to all respective control surface attach points, was confirmed. The aileron cables exhibited a tensile overload condition. The landing gear and flaps were in their retracted positions. The fuel lines and fuel valve position could not be determined due to the post impact fire. However, all fuel caps were accounted for and appeared to be in the locked position. Approximately 7 feet of aft fuselage remained; however, it had considerable thermal damage. There was approximately 3 feet of vertical stabilizer spar attached to the aft fuselage section, and the rudder trim drum was attached to the remaining spar and was found in the neutral tab position. The rudder stops were found and no marks were noted. The left wing was separated from the fuselage at the attach fittings and exhibited impact damage and post impact fire damage. The two engines were located adjacent to one another, the right engine came to rest upright, the left engine came to rest inverted, and all propeller blades remained attached to their respective propeller hubs. Both engines exhibited thermal damage throughout. Spark plugs were removed and exhibited thermal damage. Fuel ignition spider, fuel screen, and oil filter exhibited thermal damage. A follow-on examination was conducted on November 10, 2009 at a storage facility in Griffin, Georgia. Left Engine The left e