Ukiah, OR, USA
N79BF
BELLANCA 17-31ATC
On the morning of the visual flight rules flight, the non-instrument-rated pilot obtained a verbal weather briefing and stated that he planned to depart early afternoon, with an expected flight duration of about 3 hours. The pilot was advised of the possibility of turbulence and clouds along his route, which was primarily over mountainous terrain, with cloud tops forecast to be 25,000 feet and above. There were no records of any subsequent telephonic or computer weather briefings, and the pilot did not file a flight plan. Although the pilot did not communicate with air traffic control (ATC), ground-based ATC radar captured the majority of the flight. When the airplane was reported overdue by relatives of one of the passengers, the radar data were used to search for and locate the airplane, which had impacted terrain in a remote wilderness area about 110 miles from the departure airport. Evaluation of the radar data indicated that the total flight duration was about 1 hour and that the airplane was above 12,500 feet for about 28 minutes and above 14,000 feet for about 8 minutes. The last 2 minutes of radar data depicted a course reversal, followed by an erratic course and an irregular, rapid descent. Meteorological data indicated that broken or overcast cloud base altitudes ranged from about 7,000 to 10,000 feet, with tops near 28,000 feet and that icing conditions could be expected in the clouds above about 10,000 feet. Terrain elevations within 30 miles of the impact site ranged from about 4,000 to 7,000 feet. Wreckage patterns and ground scars indicated a near-vertical impact trajectory. A supplemental oxygen tank was present in the wreckage, but the tank inspection expired 8 years before the accident, and no hoses or masks were present. Postaccident examination of the airplane and engine did not reveal any preimpact mechanical malfunctions or failures that would have precluded normal operation. The radar ground track was consistent with the pilot trying to find a route clear of the clouds. The pilot's lack of an instrument rating, combined with the erratic ground track, rapid descent, and steep impact angle, indicated that the pilot lost control of the airplane after it entered clouds. Available evidence supported the likelihood of spatial disorientation, as well as the possibility of hypoxia.
HISTORY OF FLIGHT On June 11, 2011, about 1601 Pacific daylight time, a Bellanca 17-31ATC, N79BF, was substantially damaged when it descended rapidly from cruise flight, and impacted terrain in the Umatilla National Forest near Ukiah, Oregon. The owner-pilot and the two passengers were fatally injured. The personal flight was operated under the provisions of Title 14 Code of Federal Regulations Part 91, and no flight plan was filed. Airport personnel stated that the pilot kept the airplane in a hangar at The Dalles Airport (DLS), Dallesport, Washington. According to relatives of the pilot and passengers, the pilot and one of the passengers were neighbors, and that passenger reportedly asked the pilot to fly him to Casper, Wyoming, in order to attend a rodeo in which his daughter was participating. About 0800 on the morning of the accident, the pilot telephoned Lockheed Martin Flight Service (LMFS) for a weather briefing. Airport fueling records indicated that 39 gallons of fuel were purchased at DLS about 1500 the same day, and that the purchase was paid for with the passenger's credit card. Examination of ground-based radar tracking data indicated that the first target associated with the airplane was acquired at 1502, about 8.5 miles east of DLS, at an indicated altitude of 2,000 feet. The airplane followed a curving course to the southeast for another 28 miles, and then tracked straight for 53 miles, on a course of 084 degrees true. At the end of that track, the indicated altitude was 13,500 feet. The airplane then turned south, leveled at about 14,500 feet, and flew another 43 miles before it conducted a course reversal to the left. About 2 minutes later, the airplane began a rapid descent, and the last radar target was recorded at 1601, about 1,800 feet from the wreckage location. A search of Federal Aviation Administration (FAA) records revealed that the pilot did not communicate with air traffic control during the flight. The airplane was the subject of an ALNOT (Alert Notice) issued about midnight on June 11 by LMFS in Prescott, Arizona, in response to queries by relatives of a passenger. The search area was determined using a combination of radar tracking data and signal information from two cellular telephones that belonged to the airplane occupants. No emergency locator transmitter (ELT) signal from the airplane was detected. The wreckage was located about 1500 on June 12 by airborne search teams. The airplane was not insured, and lack of funding precluded airplane recovery for a detailed off-site examination. PERSONNEL INFORMATION The investigation was unable to locate any of the pilot's personal flight history documentation. According to FAA records, the pilot held a private pilot certificate with an airplane single-engine land rating. That certificate was issued in 1981. The pilot's most recent FAA third-class medical certificate was issued in February 1999. At that time, he reported 1,250 total hours of flight experience. Neither passenger held any pilot certificates. AIRCRAFT INFORMATION The airplane was manufactured in 1978, and was first registered to the pilot in 1999. It was equipped with a turbocharged Lycoming TIO-540 series engine and a three-blade propeller. The airplane was a low-wing monoplane design. Primary structure consisted of a fabric-covered steel-truss fuselage with wood- and fabric-skinned wood structure wings. The airplane had a total fuel capacity of 75 gallons, split between two main fuel tanks of 30 gallons capacity each, plus an auxiliary tank of 15 gallons capacity. The airplane was equipped with four seats (including pilot), and a supplemental oxygen system. The investigation was unable to locate any of the pilot's personal maintenance records documentation for the airplane. Airworthiness records obtained from the FAA database in Oklahoma City did not contain any documentation subsequent to the pilot's purchase of the airplane. The pre-accident airworthiness status of the airplane, including inspection history, could not be determined. METEOROLOGICAL INFORMATION Pilot's Weather Briefing The pilot telephoned LMFS about 0800 on the morning of the flight for a "weather advisory." He stated that he planned to go from DLS to Casper/Natrona County International Airport (CPR), Casper, under visual flight rules (VFR) via Boise and American Falls, Idaho. He stated that his planned departure time was 1400, and estimated his en route time as 3 hours. The route as specified by the pilot measured about 680 miles. The LMFS briefer provided information about airmen's meteorological information advisories (AIRMETs) for terrain obscuration and low level moderate turbulence that were valid for the route and time of flight, and noted that that information would be updated at 1400. The briefer noted the presence and levels (including tops to 25,000 feet) of clouds along the route of flight, as well as the possibility of thunderstorms with tops to 35,000 feet. The pilot requested the winds aloft only for 14,000 feet. There was no record that the pilot ever contacted LMFS or any other official weather-services provider subsequent to that telephone call. Weather Forecast and Observation Information The weather reporting station closest to the accident site was La Grande/Union County Airport (LGD), La Grande, Oregon, located approximately 12 miles north of the accident site. The 1555 LGD automated observation included calm wind; visibility 10 miles; ceiling overcast at 7,000 feet above ground level (agl) (about 9,700 msl); and a measured hourly precipitation of 0.01 inches. The 1615 LGD observation was similar, but with a ceiling of about 6,000 feet agl (about 8,700 feet msl). The next closest weather reporting facility was Baker City Municipal Airport (BKE), Baker City, Oregon, located approximately 18 miles southeast of the accident. The BKE terminal area forecast issued at 1021 called for visibility better than 6 miles, rain showers, and a broken ceiling at 7,000 feet agl (about 10,400 feet msl) between 1300 and 1900. The BKE forecast was amended at 1314 (about 2 hours before the departure) to include rain showers and thunderstorms, and a broken ceiling at 4,000 feet agl (about 7,400 feet msl). The 1553 BKE automated observation included wind from 180 degrees at 6 knots, visibility 10 miles in light rain, ceiling broken at 4,900 feet agl (about 8,300 feet msl), overcast at 6,000 feet (about 9,400 feet msl), and rain that ended at 1521, and began again at 1543. AIRMETs for mountain obscuration conditions, and icing conditions above 10,000 feet, were current for the flight track and flight time period. The closest upper air sounding observation was at the NWS facility at Boise, Idaho, located approximately 123 miles southeast of the accident site. The 1700 sounding implied saturated conditions or clouds between 13,000 and 19,000 feet. The freezing level was 10,422 feet and the sounding supported the existence of in-cloud icing conditions. The wind and temperature profile supported a light mountain wave scenario over the higher terrain, and downstream of the highest peaks. In addition, the wind profile supported the potential for some strong vertical wind shear and turbulence. Satellite data depicted an overcast layer of nimbostratus to towering cumulus clouds over the accident site, with cloud tops near 28,000 feet. The closest weather surveillance radar (Doppler WSR-88D) was located at Boise. The 1602 base reflectivity image for the 0.5-degree elevation scan depicted a large area of very light intensity echoes (5 to 10 dBZ) over the accident site. Echoes increased to 20 to 40 dBZ in intensity to the east and southeast, indicative of heavier precipitation. There was no lightning within 25 miles of the accident site between 1545 and 1610. Refer to the public docket for this accident for detailed weather information. AIDS TO NAVIGATION Overlay of the recovered FAA air traffic control (ATC) radar data on aeronautical navigation charts revealed that the ground tracks did not coincide with established airways, or with direct lines between ground-based navigation facilities. The investigation could not determine what means the pilot used for navigation. WRECKAGE AND IMPACT INFORMATION The wreckage was located on the side of a steep hill. Multiple trees of various heights up to 60 feet were situated in the immediate vicinity of the wreckage; no scars, or trunk or branch fractures, consistent with impact by the airplane, were observed. The airplane was situated in an upright, nose-down attitude, on a heading of approximately 150º magnetic, which was approximately perpendicular to the local terrain slope. The wreckage was very tightly contained, all major components retained their approximate relative design locations, and only a few window, door, and cowling fragments were not contained in the main wreckage. Those fragments were less than 20 feet from the wreckage. The propeller, engine, and forward fuselage were embedded in a crater about 3 feet deep and 6 feet in diameter. The front spar of each wing was located in a shallow ground scar perpendicular to the longitudinal axis of the main wreckage. The aft wing spars, as well as the wing skin, fuel tank, flap, and aileron sections were on top of or just aft of the front spars. The firewall, instrument panel, and steel tube cabin structure exhibited significant crush damage and deformation. The empennage was relatively intact. No evidence consistent with airplane rotation about the vertical axis at the time of impact was observed. All major components were accounted for at the impact site No evidence of preimpact damage, malfunction, or separation of any wing components, including the flap and aileron on each wing, was observed. The flap position at impact could not be positively determined, but the available evidence was consistent with the flaps being fully retracted. Control continuity from each aileron to the cockpit controls, as well as the aileron crossover cable assembly, was established. The position of the landing gear at impact could not be definitively determined, but the available evidence was consistent with the main landing gear in the retracted position. The vertical fin and both horizontal stabilizers remained attached to the fuselage tailcone structure, and the rudder and both elevators remained attached to their respective main airfoils. The pitch trim tab remained fully attached to the left elevator. No abnormal foreign deposits such as oil or soot, or other unusual indications, were observed on any of the exterior skin surfaces on the empennage. Control continuity from the elevators to the cockpit controls, and from the pitch trim tab to the mid-fuselage motor-gear assembly was confirmed. The rudder and elevator cables aft of the wing were observed to be properly routed through their respective pulleys, guards or fairleads. Most flight and engine instruments were damaged beyond recognition. The tachometer hour meter registered 2,977.40 hours. Damage to the instrument vacuum pump was consistent with impact. The fuel strainer screen was crushed, but clean, and the internal wall of the bowl did not exhibit any corrosion. The fuel selector valve control handle was fracture-separated from the valve. The selector valve body was captive in the crushed fuselage structure, and the setting could not be determined. The identification placard for the emergency locator transmitter (ELT) battery bore an expiration date of "August 2009." A supplemental oxygen cylinder remained attached to its mounts in the aft fuselage. The cylinder bore three stamped dates (denoting hydrostatic inspections, which are required every 5 years); the most recent one was "3-98." An oxygen outlet panel equipped with four quick-disconnect ports, one of which was labeled "PILOT," was found. No fittings or fitting remnants were found in any of the ports, and none of the ports exhibited any damage consistent with forced mechanical separation of a fitting from a port. No oxygen masks, nasal cannulas, fittings, or flexible, low-pressure oxygen distribution lines were located in the wreckage. No engine data plate was observed. One turbocharger was recovered; it exhibited some crush damage but no damage consistent with overtemperature or rotor burst. The oil filter and most engine accessories were fracture-separated from the engine. The magnetos were crushed and fractured, and could not be tested manually for rotation or function. The fuel distribution block diaphragm was intact and clean, and the valve moved freely in the block. The oil pump contained oil, and did not exhibit any corrosion or other contamination. Two spark plugs were removed and examined; both exhibited coloration and deposits consistent with normal wear. Damage to, and debris around the aft end of the engine, precluded the determination of crankshaft continuity, and pushrod damage precluded the determination of camshaft continuity. The propeller remained attached to the hub, and the hub remained attached to the engine. All three propeller blades were bent aft near the blade root, and none exhibited any twisting or chordwise scoring. All three blades appeared to be set at about the same pitch. A damaged iPhone was recovered in the wreckage, and was sent to the NTSB recorders laboratory in Washington, DC. No data was able to be obtained from the device. Refer to the accident docket for additional detailed information regarding the wreckage. MEDICAL AND PATHOLOGICIAL INFORMATION An autopsy was performed on the pilot by the Oregon Office of the State Medical Examiner. The autopsy determined that the cause of death was multiple traumatic injuries. Forensic toxicology was performed on specimens from the pilot by the FAA Civil Aeromedical Institute Bioaeronautical Sciences Research Laboratory. The toxicology report stated that no ethanol or any screened drugs were detected. ADDITIONAL INFORMATION FAA ATC Radar Tracking Data The pilot had not requested any services from, nor was he in communication with ATC, but his transponder was set to the 1200 VFR code, in the altitude-reporting mode. There was no evidence to suggest that the flight was actively monitored by ATC personnel, nor was it required. Once the airplane was determined to be missing, a search of recorded radar data for the date, time, and departure location revealed that the flight had been tracked and recorded by FAA ground-based radar facilities. The first transponder-reply radar return associated with the airplane was acquired about 1502, when the airplane was about 8.5 miles east of DLS, and climbing through a transponder-indicated altitude of about 2,000 feet. The airplane followed a curving course to the southeast for 28 miles (12 minutes), and then tracked straight for 53 miles (23 minutes), on a course of 084 degrees true. At the end of that track, the indicated altitude was 13,500 feet. The airplane then turned south, climbed to and leveled at about 14,500 feet, and flew another 20 minutes and 43 miles before it conducted a course reversal to the left. The last radar return at 14,000 feet was recorded at 1558:59. Only 12 additional returns, evenly spaced at about 4-second intervals, were recorded. The altitude data associated with those points varied irregularly between 12,100 feet and 9,900 feet, but indicated an overall rapid descent; two of the returns did not have altitude data associated with them, consistent with rapid maneuvering or a possible unusual attitude of the airplane. The last radar target was recorded about 1601, about 1,800 feet from the ground impact location. The total duration of the flight was about 1 hour. Hypoxia and Oxygen Requirements According to FAA publication FAA-H-8083-25, Pilot's Handbook of Aeronautical Knowledge (PHAK), "the word "hypoxia" means "reduced oxygen" or "not enough oxygen." Although any tissue will die if deprived of oxygen long enough, usually the most concern is with getting enough oxygen to the brain, since it is particularly vulnerable to oxygen deprivation. Any reduction in mental function while flying can result in life threatening errors. Hypoxia can be caused by several factors, including an in
The non-instrument-rated pilot's decision to conduct a visual flight rules flight over mountainous terrain into a region covered by clouds, which likely resulted in spatial disorientation and subsequent loss of airplane control.
Source: NTSB Aviation Accident Database
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