WPR18FA035

The pilot's loss of situational awareness shortly after takeoff over a sparsely lit area in dark night conditions, which resulted in a rapid descent to ground impact.

The private pilot departed on a personal flight in visual meteorological conditions during the early evening and flew to a nearby airport, where he parked the airplane and walked to a nearby restaurant. He returned to the airplane about an hour later, which was about 20 minutes after the end of civil twilight. Surveillance video captured the accident airplane depart the runway and enter a right traffic pattern, which was the opposite of the published left traffic pattern and took the airplane over unlit pasture and hills. The imagery then depicted the airplane enter a rapid descent on what appeared to be the right downwind leg of the traffic pattern. The airplane disappeared from view consistent with ground impact. The descent duration was about 7 seconds. The airplane impacted a pasture north of the airport. The debris field indicated that the airplane impacted the ground with a relatively shallow flight path angle, in a nose- and right-wing low attitude, with a significant amount of horizontal energy. All major airplane and engine components were identified in the wreckage, and no indications of any pre-impact mechanical deficiencies or failures were observed. The flaps were in the fully retracted position, which was the climb-cruise configuration, likely indicative that the pilot was not attempting a landing when the impact occurred. The undamaged condition of the artificial horizon gyro rotor and internal case suggested a possibility that the device was not operating, but the actual operating status of the instrument at the time of the accident could not be determined. Even if the artificial horizon was inoperative, external visual references should have been sufficient to enable the pilot, albeit possibly with some difficulty, to maintain the proper airplane attitude and flight path. Some fibrous lint-like material was found in the carburetor fuel inlet screen; the material was foreign to the airplane fuel system, but it was not determined when or by what means the lint was introduced into the system. The lint did not appear to have any adverse effect on engine operation; propeller damage was consistent with the engine developing significant power at the time of impact. Airplane fueling information and published performance data indicated that the airplane had sufficient fuel onboard for a return flight to the airport of origin. About 5 weeks before the accident, the pilot had completed a night flight in the accident airplane from his home airport to the accident airport and back, which indicated that he was at least somewhat familiar with the accident airport. The reason for the pilot's use of a right traffic pattern instead of the designated left traffic pattern for his departure could not be determined. Although the pilot had documented color vision deficiencies, this condition likely did not contribute to the accident sequence. The pilot had relatively limited total and night flying experience, and the night and local terrain were very dark. Given the signatures of engine power and lack of mechanical anomalies found during postaccident examination, it is not likely that the accident was the result of a loss of engine power. Further, correlation of debris field information with the descent angle depicted in the surveillance imagery frames indicated that the descent path was too shallow to be consistent with an aerodynamic stall. Additionally, the airplane's impact attitude and the distribution of the wreckage were inconsistent with a loss of control due to spatial disorientation. It is possible that the pilot lost his situational awareness while maneuvering onto the right downwind leg which resulted in the airplane descending rapidly to ground impact.

The Kern County, Bakersfield, California, Sheriff-Coroner's Office autopsy report indicated that the cause of death was "blunt injuries," and that there were "no signs of natural disease such as to qualify as clues to a cause of the accident." FAA medical records indicated that the pilot had failed the color vision test on the four medical certificate applications that were on file. His FAA medical examiner(s) did not identify any significant adverse conditions, and his most recent third-class FAA medical certificate was issued in April 2016. Toxicology testing of the pilot's tissue samples at the FAA Forensic Sciences Laboratory was negative for carbon monoxide and ethanol. Ranitidine was detected in urine and blood samples. This medication is used to treat intestinal ulcers, gastroesophageal reflux disease, heartburn associated with acid indigestion, and other conditions where the stomach produces too much acid. The FAA has no limitations on its use by pilots. The 1755 TSP automated weather observation included winds from 320° at 3 knots, visibility 10 miles, clear skies, temperature 7° C, dew point 0° C, and an altimeter setting of 30.13 inches of mercury. Local sunset occurred at 1646, and civil twilight ended at 1713. The moon was a waxing crescent with 2% of its disc illuminated. Local moonset occurred at 1802. Federal Aviation Administration (FAA) records indicated that the pilot held a private pilot certificate with an airplane single-engine land rating. At the time of the accident, the pilot had logged a total flight experience of about 152 hours, including about 12 hours of night experience. His most recent flight review was completed in August 2017. On October 8, 2017, he had flown solo in the accident airplane from WJF to TSP and back at night and conducted 3-night landings. The initial impact point was located about 350 ft west-northwest of, and offset about 2,050 ft north-northwest of, the runway 11 threshold. The accident site terrain was hard-packed, dry earth, flat and level, with mostly dried grass and some low, dried shrubs. All airplane components were accounted for at the accident site. No evidence consistent with in-flight fire or in-flight structural failure was observed. Ground scars were consistent with the airplane impacting the terrain in a nose- and right-wing-low attitude. The right wingtip strike was the beginning of the ground scar. The earliest identifiable piece of wreckage was an outboard fragment of the right aileron. A ground scar consistent with the right main landing gear (RMLG) was located about 20 ft beyond the right wingtip strike. Scarring consistent with nose landing gear or propeller contact began about 10 ft beyond the RMLG strike. The ground scars and airplane damage were consistent with the wreckage tumbling and sliding before coming to rest. The main wreckage consisted of the engine, wings, empennage, and most of the fuselage. The main wreckage came to rest about 250 ft, on a bearing of 138° true, from the initial impact point. Several items, including the propeller, some engine accessories, and some fuselage fragments, formed a debris field between the initial impact point and the main wreckage. The debris field orientation was within about 14° of the runway alignment. Several high-density items such as the battery and the alternator core came to rest several hundred feet beyond the main wreckage. Both wings exhibited full-span, aft-direction crush damage along their leading edges. Both lift struts remained attached to their respective wings but were separated from the fuselage. Both wings retained their respective fuel tank caps. Both flaps remained fully attached to their respective wings; the flaps were relatively undamaged and were found in positions consistent with being fully retracted at the time of impact. Both ailerons remained attached to their respective wings. The vertical stabilizer with rudder and horizontal stabilizers with the elevators remained attached to the aft fuselage. The pitch trim tab remained attached to the right horizontal stabilizer. All wing and empennage control surfaces retained their respective balance weights. Control continuity was established from both ailerons to the fuselage break in the cockpit. Control continuity was established from both elevators, the pitch trim tab, and the rudder to the fuselage break in the cockpit. The cockpit/cabin was found torn open. The windshield was reduced to numerous smallfragments. Both cabin doors were completely fracture-separated from the airplane. The flap handle was found in the "Up/Retract" position. The elevator trim indicator and trim wheel were impact damaged. The trim actuator measurement indicated a 5º-tab-trailing-edge-up position. The control lock was found stowed in the back pocket of the right seat. The primer, throttle, and mixture controls in the cockpit were found in their full forward positions; the throttle and mixture cables were continuous to the carburetor. The carburetor heat control was not identified in the wreckage. The fuel selector was found in the "ON" position. The master switch and all circuit breakers were absent from their receptacles. The ignition switch was found in the "OFF" position with the key installed and bent to the left. The engine remained partially attached to the engine mount and forward fuselage. The engine was relatively intact, but sustained impact damage in the aft and up directions. There was significant ductile bending of the exhaust system components. Several engine accessories or external components were fracture-separated from the engine. There was no evidence of abnormal external oil streaking observed on any of the airplane skins. No evidence of any pre-impact catastrophic failures was observed. The vacuum pump remained securely attached to its mounting pad on the engine accessory face. The pump was removed and disassembled. The shear coupling, rotor, and vanes were all intact. The rotor rotated freely by hand, and all vanes moved freely in their slots. The artificial horizon was fracture-separated from its mount and was missing its face. The gyro rotor case was opened for examination and no internal scoring or other damage was observed. The engine was separated from the attached wreckage for further examination. The top spark plugs were removed and examined; their appearance was consistent with normal operation. The crankshaft was rotated manually and freely in both directions. Thumb compressions was obtained in proper sequence on all four cylinders. Clean, uncontaminated oil was observed at all four rocker box areas. Mechanical continuity and proper operational sequence were established throughout the rotating group, valve train, and accessory section. The combustion chamber of each cylinder was examined via borescope; all cylinders and valves exhibited normal operational signatures, and no damage was observed. No oil residue was observed in the exhaust system gas path. The oil displayed evidence of metal contamination. Examination of the gascolator screen and the forward and aft strainers at each wing tank found no visible contaminants. The engine compartment fuel line was found to be in place and secure at its respective B nuts; however, the fitting at the carburetor inlet was fracture-separated, consistent with overload. The carburetor was undamaged and remained securely attached to the engine. Reliable positions of the mixture and throttle settings at the time of impact could not be determined. No external fuel staining was observed on the carburetor. The carburetor was opened for examination. All internal locking tabs and safety devices of the carburetor were in place and properly secured. The fuel bowl was free of visible contaminants. The float assembly remained secure at the mounting and free of damage. The metal float pontoons exhibited no evidence of rubbing against the wall of the bowl. The right float