CEN14FA506

The pilot's continued visual flight into instrument meteorological conditions, which resulted in his failure to maintain clearance with trees and terrain.

The instrument-rated pilot obtained weather information about 1 hour 45 minutes before takeoff. The weather information included an AIRMET that indicated that instrument flight rules (IFR) conditions existed at the takeoff and destination locations and along the intended route of flight due to precipitation and mist. No evidence was found indicating that the pilot obtained additional weather information. Radar data showed the airplane proceeding toward the destination airport until about 22 miles from the destination, at which point the airplane began a series of turns for undetermined reasons before attempting an approach to a different airport. Radar data then showed the airplane enter a climbing turn away from the airport that did not follow any published missed approach procedure. Shortly after performing the turn, the airplane collided with trees and terrain. There is no evidence that the pilot attempted to obtain an IFR clearance or made any distress calls. Examination of the airframe and engine did not reveal any anomalies that would have precluded normal operation. The pilot had several medical conditions; however, there is no evidence that a medical condition contributed to the accident.

KOKM is a public airport located at an elevation of 720 feet. It is attended from Monday through Saturday from 0900-1800. It is serviced by runway 18-36 which is 5,150 feet by 101 feet, constructed of concrete, and illuminated by medium intensity runway lighting. Runway 18 has medium intensity approach lighting system with runway alignment indicator and sequenced flashing lights. The lights are preset to low intensity and can be increased in intensity via common traffic advisory frequency (CTAF). Three instrument approach procedures exist for KOKM, the ILS/LOC and RNAV (GPS) approaches to runway 18 and VOR-A to the aerodrome. The ILS 18 is the most precise approach with the lowest weather minimums at a 200 feet ceiling and ½ mile visibility. Radar information There was no record of the pilot talking to any tower or air traffic control personnel. Radar information was examined for evidence of the accident airplane's flight. About 0503 CDT, an airplane transmitting the beacon code 1200 was recorded departing from KFWS to the southeast before turning north bound. The airplane proceeded towards KRVS at an altitude between 2,500-4,000 feet mean sea level. When the airplane was over Beegs, Oklahoma, it began to make several turns. It approached the town from the south about 3,600 feet msl and made 360° turn (with about a 1 mile diameter) and descended to 2,200 feet msl. The airplane then flew another 360° turn that increased in diameter and descended to 1,900 feet msl. Next, the airplane performed a teardrop turn that descended to 1,300 feet msl (about 430 feet agl) before climbing to 1,700 msl and leaving Beegs to the northeast. The airplane then flew west of the initial approach points for the instrument approaches to KOKM. At 0731:52, the airplane was at 1,200 feet msl (about 325 feet agl) and momentarily disappeared from radar and reappeared at 0733:41 at an altitude of 1,300 msl. It appeared to be flying southeast before it made a slight S-turn towards the southwest and began to climb. Then the airplane turned to the northwest away from the airport. The last radar return occurred at 0736:29 as the airplane is flying to the north at an altitude of 1,700 msl. This last return was about ½ miles east of accident site. The lowest cloud layer in this area was an overcast ceiling of 900 ft msl or about 200 ft above ground level. During the airplane's maneuvering north of OKM, it never aligned with the runway extended centerline and the maneuver to the northwest was not consistent with any published missed approach procedure. An autopsy was authorized and conducted on the pilot by the Office of the Chief Medical Examiner, Tulsa, Oklahoma. The autopsy noted the presence of mild atherosclerotic stenosis of the left anterior descending coronary artery. In addition, concentric left ventricular hypertrophy consistent with hypertensive cardiomyopathy was also noted. The cause of death was due to multiple blunt force injuries. The manner of death was ruled an accident. The FAA Civil Aerospace Medical Institute performed forensic toxicology on specimens from the pilot. The specimens received displayed evidence of putrefaction. The report listed the following results: 53 (mg/dL, mg/hg) Ethanol detected in Blood (Cavity) 15 (mg/dL, mg/hg) Ethanol detected in Kidney NO ETHANOL detected in Liver N-Propanol detected in Blood (Cavity) Atenolol detected in Liver and Blood (Cavity) Diphenhydramine detected in Liver 0.034 (ug/ml, ug/g) Diphenhydramine detected in Blood (Cavity) Irbesartan detected in Liver and Blood (Cavity) Rosuvastatin detected in Liver and Blood (Cavity) Due to a lack of ethanol in the liver, it is likely that the ethanol was from sources other than ingestion. Diphenhydramine is a common over the counter antihistamine used in the treatment of the common cold and hay fever. Irebesatan is used mainly for the treatment of hypertension. Rosuvastatin is used to treat high cholesterol and related conditions, and to prevent cardiovascular disease. On his most recent medication application, dated November 15, 2012, the pilot reported the use of irbesatan and rosuvastatin. In addition, the pilot reported the use of insulin glargine, insulin aspart injection, canagliflozin, testosterone, niacin, and montelukast. The pilot provided documentation to maintain his special issuance for type II diabetes which included an eye evaluation, glaucoma evaluation, as well as information from his endocrinologist. The FAA's Aerospace Medical Certification Division renewed the pilot's special issuance on February 11, 2014. A review of the pilot's medical information found no evidence of a medical condition contributing to the accident. The airplane wreckage was located in a field surrounded by trees in an area of rolling hills. The wreckage path followed a 110 degree heading and was about 3.5 miles northwest of the Okmulgee Regional Airport (KOKM). The first impact points consistent of tall trees. A portion of the right elevator was located in one of the trees. About 75 feet from the tree line was a ground scar. Impact signatures were consistent with impact of the fuselage at a 10° nose low attitude. The propeller was impact separated at the propeller hub and was located at the end of the ground scar. The right wing separated from the fuselage and was fractured into two major portions outboard of the wing strut. These portions contained at least two semi-circular indentions consistent with tree strikes. The main wreckage came to rest about 210 feet past the ground scar. It consisted of the cockpit area, fuselage, and empennage. The horizontal stabilizer, rudder, vertical stabilizers and elevators had separated just aft of the empennage but remained attached to the airplane by their flight control cables. The inboard portion of the left wing, to include the aileron and flap were located just northwest of the main wreckage. The engine and firewall had separated from the airplane and came to rest about 25 feet past the main wreckage in a tree line. There were multiple fractures in both aileron control cables. All fractures displayed broomstrawing of the cables. Control continuity was established from the cockpit controls to the elevator and rudder flight control surfaces. The flap actuator indicated that flaps were up. Elevator trim was found at neutral (0°). The cockpit instruments were largely impact damaged and unreadable. The engine was examined on-scene. Engine continuity and thumb compression was established. The propeller had sheared from the engine at the propeller flange. Both magnetos and the engine driven fuel pump were impact separated and destroyed. The throttle body was impact damaged. Both blades of the propeller displayed s-bending, curling, polishing, chordwise scratches and angular scratches. No preimpact anomalies were detected with the engine or airframe. The airplane was equipped with a Garmin G1000 integrated avionics system. The G1000 was impact damaged and the secure digital memory card containing flight information was not located. Only the map database memory was located in the wreckage. According to electronic records, the pilot obtained Direct User Access Terminal Service (DUATS) flight information to include weather at 0311:34 and that online session terminated at 0311:37. During that information exchange, DUATS provided terminal aerodrome forecast (TAF) for KRVS that stated the forecast from 0300 CDT onward expected a calm wind, 4 miles visibility and mist, scattered clouds at 2,500 feet above ground level (agl). Temporary conditions of 1 mile visibility, mist, and scattered clouds at 500 feet agl were forecast between 0500 and 0900 CDT. In addition, Airmen's Meteorological Information (AIRMET) was provided for instrument flight rules conditions of ceilings below 1,000 feet agl and visibility below 3 miles due to precipitation and mist for the pilot's intended route of flight. The pilot intended route of