N79BFCessna 550 · 2004

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.

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.

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.

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.

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.

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.

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.

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 insufficient supply of oxygen."

The document further stated that "All pilots are susceptible to the effects of oxygen starvation, regardless of physical endurance or acclimatization. When flying at high altitudes, it is paramount that oxygen be used to avoid the effects of hypoxia" and as "altitude increases above 10,000 feet, the symptoms of hypoxia increase in severity."

Paragraph 91.211 ("Supplemental Oxygen") of the Federal Aviation Regulations required that the pilot be provided with and use supplemental oxygen for that part of the flight that was of more than 30 minutes duration at cabin pressure altitudes above 12,500 feet and up to and including 14,000 feet, and continuously at cabin pressure altitudes above 14,000 feet.

Spatial Disorientation

According to the PHAK, "spatial disorientation specifically refers to the lack of orientation with regard to the position, attitude, or movement of the airplane in space…. During flight in visual meteorological conditions (VMC), the eyes are the major orientation source and usually prevail over false sensations from other sensory systems. When these visual cues are taken away, as they are in instrument meteorological conditions (IMC), false sensations can cause a pilot to quickly become disoriented."

The PHAK then stated that "Prevention is usually the best remedy for spatial disorientation. Unless a pilot has many hours of training in instrument flight, flight in reduced visibility or at night when the horizon is not visible should be avoided."

VFR into IMC

Chapter 16 ("Emergency "Procedures") of the FAA publication Airplane Flying Handbook (AFH, FAA-H-8083-3A) contained a section entitled "Inadvertent VFR Flight into IMC," which stated that "Accident statistics show that the pilot who has not been trained in attitude instrument flying, or one whose instrument skills have eroded, will lose control of the airplane in about 10 minutes once forced to rely solely on instrument reference." The stated purpose of the AFH was "to provide guidance on practical emergency measures to maintain airplane control for a limited period of time in the event a VFR pilot encounters IMC conditions…to help the VFR pilot keep the airplane under adequate control until suitable visual references are regained."

The AFH stated that the first steps necessary for a VFR pilot to survive an encounter with IMC included "recognition and acceptance of the seriousness of the situation and the need for immediate remedial action, maintaining control of the airplane, and obtaining the appropriate assistance." It stated that "Attempts to control the airplane partially by reference to flight instruments while searching outside the cockpit for visual confirmation of the information provided by those instruments will result in inadequate airplane control," which "may be followed by spatial disorientation and complete control loss." The AFH emphasized that the pilot "must understand the most important concern—in fact the only concern at this point—is to keep the wings level. An uncontrolled turn or bank usually leads to difficulty in achieving the objectives of any desired flight condition."

The guidance then discussed emergency airplane attitude control, and how to achieve and maintain it. It instructed pilots to "make use of any available aid in attitude control such as autopilot or wing leveler."