Primary finding
Probable cause
The noninstrument-rated pilot’s decision to continue visual flight rules flight in instrument meteorological conditions, which resulted in a loss of control due to spatial disorientation.
Investigator assessment
Analysis narrative
The noninstrument-rated private pilot was nearing the destination airport at the end of a cross-country flight. Instrument meteorological conditions (IMC) were widespread in the vicinity of the destination, and several witnesses stated that the weather conditions were misty, foggy, and rainy at the time of the accident. However, the extent to which the pilot had familiarized himself with the weather conditions along the route of flight before takeoff could not be determined, as there was no record of a weather briefing from an official, access-controlled source. Radar data showed the airplane on a northerly heading at a cruise altitude about 7,000 ft above ground level (agl). The airplane passed west of the airport as it continued north, then entered a descending right turn in the direction of the airport. The airplane conducted a series of descending right and left turns east of the airport until radar contact was lost at an altitude about 5,600 ft agl in the vicinity of the accident site. The pilot did not contact air traffic control at any time during the flight. The airplane came to rest in heavily wooded, hilly terrain and was highly fragmented. There was no evidence of an in-flight breakup, or of pre- or postimpact fire. Several angularly-cut tree branches along the wreckage path indicated that the engine was producing power at the time of impact. A postaccident examination of the airplane and the engine revealed no evidence of any anomalies that would have precluded normal operation. It is likely that the pilot was operating in visual meteorological conditions above the clouds until he neared the destination airport, at which time he attempted to descend through IMC in order to land. The fact that the pilot did not hold an instrument rating and had received only minimal training in instrument flight significantly increased his susceptibility to the sensory illusions associated with instrument flight. Given the reduced visibility conditions and the radar flight track of the airplane, it is likely that the pilot experienced spatial disorientation and a subsequent loss of control as he attempted to descend through IMC and locate the airport.
Source record
Factual narrative
Wendell H. Ford Airport (CPF) was located about 1 statute mile southwest of the accident site at an elevation of 1,256 feet msl. The airport was comprised of two asphalt runways, oriented 14/32 and 06/24. Runway 14/32 was 5,499 feet long by 100 feet wide. Runway 06/24 was 3,246 feet long by 60 feet wide. Runways 14 and 32 were equipped with pilot-controlled lighting, which included precision approach path indicator lights for each runway. Spatial Disorientation The Airplane Flying Handbook (FAA-H-8083-3A) stated, "…the VFR pilot is, in effect, in IMC anytime he or she is inadvertently, or intentionally for an indeterminate period of time, unable to navigate or establish geographical position by visual reference to landmarks on the surface. These situations must be accepted by the pilot involved as a genuine emergency, requiring appropriate action…If the natural horizon were to suddenly disappear, the untrained instrument pilot would be subject to vertigo, spatial disorientation, and inevitable control loss." The FAA Pilot's Handbook of Aeronautical Knowledge, chapter 16, "Aeromedical Factors," stated, "Under normal flight conditions, when there is a visual reference to the horizon and ground, the sensory system in the inner ear helps to identify the pitch, roll, and yaw movements of the aircraft. When visual contact with the horizon is lost, the vestibular system becomes unreliable. Without visual references outside the aircraft, there are many situations in which normal motions and forces create convincing illusions that are difficult to overcome…Unless a pilot has many hours of training in instrument flight, flight should be avoided in reduced visibility or at night when the horizon is not visible." An autopsy was performed on the pilot's remains by the Office of the Associate Chief Medical Examiner, Frankfort, Kentucky. The cause of death was listed as multiple blunt force injuries. The FAA's Civil Aerospace Medical Institute performed forensic toxicology testing on specimens from the pilot, and no drugs of abuse were detected. The wreckage was located about 1 nm east of CPF in heavily wooded, hilly terrain. The airplane's initial impact point was identified as a tree, passed which the wreckage path extended on a heading of about 084 degrees magnetic. Several angularly-cut tree branches were identified along the wreckage path that exhibited paint transfer consistent with propeller contact. The main wreckage came to rest about 70 feet passed the initial impact point, and was destroyed by impact. All major components of the airplane were accounted for at the scene. The propeller remained attached to the crankshaft. The spinner was impact separated and only the spinner back plate remained. Both propeller blades exhibited significant s-bending, leading edge gouging, and chordwise scratching. One blade tip was impact separated approximately 22 inches from the hub. The engine was separated from the airframe and heavily impact-damaged and covered with dirt and vegetation found near the accident site. All engine accessories, with the exception of the base of the engine driven diaphragm fuel pump and a lever arm, were separated on impact. The #1 cylinder head was impact-damaged which revealed the top of the piston, exhaust valve, and intake port. The #2, #3, and #4 cylinders were inspected using a digital video borescope and revealed no anomalies. Due to impact damage, the crankshaft could not be rotated via the prop or with a spline gear tool inserted at the vacuum pump drive. The vacuum pump was intact, and examination revealed no anomalies. Impact damage precluded examination of the flight instruments. There was no evidence of any pre- or post-impact fire. The 1745 weather observation at CPF included wind from 310 degrees at 7 knots, 5 statute miles visibility, a broken cloud layer at 1,000 feet, an overcast ceiling at 1,500 feet, temperature 12 degrees C, and dew point 11 degrees C. The 1845 weather observation at CPF included wind from 330 degrees at 4 knots, 3 statute miles visibility, light drizzle, scattered clouds at 800 feet, a broken cloud layer at 1,400 feet, and an overcast ceiling at 2,100 feet. The 1905 weather observation at CPF included wind from 320 degrees at 4 knots, 3 statute miles visibility, drizzle, broken cloud layers at 800 feet and 1,200 feet, an overcast cloud layer at 2,000 feet, temperature 11 degrees C, and dew point 11 degrees C. The 1848 weather observation at JKL, located about 13 nautical miles (nm) north-northwest of the accident site, included wind variable at 5 knots, 5 statute miles visibility, mist, clouds broken cloud layers at 800 feet and 2,500 feet, and an overcast ceiling at 3,000 feet. The cloud ceilings were reported variable between 400 feet and 1,100 feet. The 1853 weather observation at JKL included wind from 310 degrees at 5 knots, 5 statute miles, mist, broken cloud layers at 800 feet and 2,700 feet, and an overcast ceiling at 3,500 feet. The cloud ceilings were reported variable between 400 feet and 1,100 feet. A terminal aerodrome forecast (TAF) for JKL, issued at 1320, forecast conditions at 1800 with visibility better than 6 statute miles and an overcast layer at 1,500 feet. Airmen's Meteorological Information (AIRMET) Sierra, issued at 1645 and valid at the accident time, was the only AIRMET valid for the accident site at the accident time. AIRMET Sierra forecasted mountains to be obscured by cloud cover. An area forecast issued at 1445 and valid for the accident time forecast occasional visibility down to 5 statute miles, mist, and an overcast ceiling between 2,000 and 2,500 feet mean sea level (MSL) with cloud tops between 6,000 and 8,000 feet MSL. An Area Forecast Discussion issued by the Jackson, Kentucky National Weather Service office at 1537, discussed IMC, including low-level cloud cover and areas of drizzle, to continue through the afternoon and evening. Dense fog was forecast to develop as the cloud ceilings lifted overnight and in the pre-dawn hours. There was no record of the pilot receiving a preflight weather briefing from a Flight Service Station or through the DUAT system. The airplane was manufactured in 1979, and was equipped with a Lycoming O-320 series, 150 hp reciprocating engine. The airplane's most recent annual inspection was completed August 1, 2014, at a total aircraft time of 2,136.75 hours. According to the owner, the airplane was equipped with Garmin 430 and 496 units, and was capable of receiving XM satellite weather information. The airplane was also equipped with an autopilot that "did not work well" and "would put the airplane into a bank." According to the owner, the pilot was aware of the limitations of the autopilot and was likely not using it during the flight. On May 21, 2015, about 1854 eastern daylight time, a Gulfstream American Corp AA-5A, N26886, was destroyed when it impacted terrain while maneuvering near Rowdy, Kentucky. The private pilot was fatally injured. Instrument meteorological conditions (IMC) prevailed, and no flight plan was filed for the flight, which departed Aiken Municipal Airport (AIK), Aiken, South Carolina, at an unknown time, and was destined for Wendell H Ford Airport (CPF), Hazard, Kentucky. The personal flight was operated under the provisions of Title 14 Code of Federal Regulations Part 91. Radar data obtained from the Federal Aviation Administration (FAA) revealed a track of visual flight rules (VFR) targets correlated to be the accident airplane. About 1830, the airplane was established on a track of about 345 degrees towards CPF at an altitude of 8,300 feet mean sea level (msl). The airplane passed west of the airport, then about 1845, about 2 miles northwest of the airport, the airplane began a right, 180-degree turn and descended to about 7,700 feet msl as it tracked south. At 1848, on an approximate right base position in relation to runway 32, the airplane began another righ