WPR14FA188

The non-instrument rated pilots’ decision to continue flight into known instrument meteorological conditions over mountainous terrain, which resulted in controlled flight into terrain.

The two pilots were on a multi-leg cross-country trip in the airplane to visit friends and relatives. Both pilots had current medical certificates, and it could not be determined who was acting as pilot-in-command at the time of the accident. The pilot seated in the right front seat had owned the airplane for over 20 years and had accumulated considerable experience flying it. Neither pilot had an instrument rating. Postaccident review of meteorological information indicated that at the time of the flight's departure, the departure and arrival airports were reporting visual meteorological conditions; however, the initial segment of the flight required flight over mountainous terrain where instrument meteorological conditions (IMC) and mountain obscuration existed. There was no record of either pilot having obtained an official weather briefing before the flight; however, they were most likely aware of the mountain obscuration, as it would have been visible before takeoff and during the initial stages of the flight. The airplane was equipped with a panel-mounted GPS receiver that was capable of providing minimum safe altitude information along a user-defined flight plan, but it is unknown if the pilots were using this feature. An iPad, which the pilots reportedly used for navigation, was found in the cockpit; however, impact damage to the device prevented determination of what navigation software was installed. Additionally a sectional chart covering the accident area was on board; however, the chart was found stowed in the rear pocket of the left front seat, indicating that the pilots were not using it during the flight. Radar and weather data revealed that the airplane entered the clouds shortly after takeoff. The flight track began to waver slightly about 7 minutes after takeoff, likely due to the airplane being hand-flown as it entered IMC. The flight track remained generally on course toward the destination airport as the flight progressed, and there was no indication of an attempt to return to the departure airport. The airplane flew through the mountainous terrain at a fairly consistent altitude about 2,500 ft below the maximum elevation figure of 12,500 ft mean sea level shown on the sectional aeronautical chart for the area and eventually struck the side of a mountain about 430 ft below its summit. The consistency of the airplane's flight track indicates that the pilots most likely intentionally elected to enter IMC in an effort to fly over the mountainous terrain and into the clearer weather beyond. The airplane's altimeter was set to the correct pressure, and postaccident examination did not reveal any anomalies with the airframe or engine that would have precluded normal operation. The investigation was unable to determine why the pilots elected to fly at an altitude below the maximum elevation for the area. While both pilots had reported histories of significant cardiovascular disease, autopsies and toxicological analysis did not reveal any findings that would have contributed to the accident. Although ethanol was detected in the right-seat pilot's urine, the levels were not sufficient to have caused impairment.

Examination The remote location of the airplane, along with treacherous snow conditions prevented an examination at the site immediately following the accident. The airplane was not insured, and therefore could not be recovered in a timely manner. As such, the entire examination was performed at the accident site by the NTSB investigator-and-charge and an FAA inspector on July 16, 2014. Fuselage The cabin sustained crush damage from the firewall through to the rear windows. The instrument panel along with all cabin flight controls were crushed and fragmented. The tail cone had buckled forward and was twisted 15 degrees along its longitudinal axis to the right. Fragments of composite spinner material, as well as paint chips, scat tube, and rubber engine mounts were located in the soil about 5 ft in front of the engine. Shredded fragments of the engine cowling were located surrounding the primary wreckage, with the furthest piece located in the bowl area about 100 ft above the engine. A total of nine pieces of luggage were located in the aft cabin, with a total weight of about 70 pounds. The throttle, mixture, propeller and carburetor heat controls were all in the full forward position. Right Wing The right wing, which separated at the wing root, had slid past the fuselage since the day of the accident, and was located 25 ft to the south. The wing sustained significant leading edge crush, with the outboard section bent 90-degrees-aft midspan. The main landing gear remained within the well. The flap had detached, and was separated into two sections; the outboard of which was located adjacent to the cabin, with the inboard section just behind the tail section. The aileron was located midway between the wing and cabin. Left Wing At the time of the examination, the outboard section of the wing had slid about 300 ft down the mountain slope. According to search and rescue personnel, it slid down due to rotor wash from the recovery helicopter. The wing had separated from the spar at the wheel well, where it exhibited upwards and aft bending damage at its root. The inboard section of the wing remained attached at the fuselage and exhibited crush damage, which had forced the leading edge skins up and over the spar. The main landing gear assembly had separated from the spar, and was located next to the engine. Empennage The vertical and horizontal stabilizers remained attached to the tailcone, with all of their respective control surfaces attached. The empennage assembly remained attached, and control tube continuity was established from the control surfaces through to the aft cabin. The surfaces moved smoothly when pushed by hand. Engine The engine sustained minimal damage, exhibited no indications of catastrophic failure, and remained partially attached to the firewall. The carburetor had separated at the intake manifold, and had become detached from the inlet filter box, which was crushed. The forward pushrods for cylinders number 2 and 4 (inlet pushrod #2, exhaust pushrod #4) exhibited aft curvature. Both magnetos remained firmly attached to their pads, with all respective spark plug wires intact. All top sparks plugs, and the bottom spark plugs for cylinder 1 and 3, were removed and examined. All plugs exhibited normal to worn-out normal wear signatures when compared to the Champion AV-27 Aviation Check-A-Plug chart. The engine's position and weight prevented complete rotation of the crankshaft at the accident site, however, the propeller could be partially rotated and exhibited free and smooth movement, with drive train continuity confirmed to the magnetos. All fuel lines from the firewall through to the engine driven fuel pump and carburetor were intact and tight at their fittings. The carburetor and both magnetos were removed for follow up examination. The propeller remained attached to the engine crankshaft and appeared to have sustained minimal damage. The composite spinner had fragmented, with additional shards located underneath the propeller hub. Examination of the airframe and engine did not reveal any anomalies which would have precluded normal operation. A complete report is contained within the public docket. Maximum Elevation Figures According to the Great Falls Sectional Aeronautical Chart that was current at the time of the accident, the depicted Maximum Elevation Figure in the area of the accident site was 12,500 ft mean sea level (msl); the accident site was located at 9,970 ft. The route of flight spanned the Great Falls and Salt Lake City Sectional Charts. Although a full complement of charts was located in the rear pocket of the forward left seat, the only chart located in the forward cabin area was for Seattle. A postmortem examination was performed by Forensic Medicine and Pathology PLLC of Billings Montana. The cause of death for both occupants was reported as the result of multiple blunt traumatic injuries. Findings for the pilot/owner included hypertensive cardiovascular disease, with severe hypertensive, and atherosclerotic cardiovascular disease reported for the pilot/pilot rated passenger. Toxicological tests on specimens recovered from both occupants, were performed by the FAA Civil Aerospace Medical Institute. Analysis revealed no findings for carbon monoxide. For the pilot/owner, analysis revealed the following findings: >> 10 (mg/dL, mg/hg) Ethanol detected in Urine >> NO ETHANOL detected in Blood (Cavity) >> NO ETHANOL detected in Muscle >> Losartan detected in Urine >> Losartan detected in Blood (Cavity) For the pilot/pilot rated passenger, analysis revealed the following findings: >> NO ETHANOL detected in Vitreous >> Atenolol detected in Urine >> Atenolol detected in Blood (Cavity) Refer to the toxicology report in the public docket for specific test parameters and results. The airplane was located 44 miles west of Cody. Shortly after it was discovered, photographs were taken from a helicopter by the Park County Office of Homeland Security, which revealed that it was covered in snow that obscured the lower forward section of the cabin along with the left wing. The main wreckage came to rest facing uphill on a 30-degree slope, at the base of a steeper 45-degree sloping bowl area. The main cabin was upright on a heading of about 290 degrees magnetic, and the crushed remnants of the right wing outboard of the main landing gear were located about 80 ft to the left and uphill of the cabin. At that time, the left wing could not be located. Search and rescue personnel reported that the snow depths in the area ranged from 3 to 5 ft. The occupants were removed from the airplane about 3 weeks after the accident, once the snow had melted sufficiently to allow safe access to the site. By that time the left wing outboard of the main landing gear was located in between the fuselage and the right wing. The outboard section of the wing was almost completely undamaged, with its aileron still attached; the corresponding left flap remained intact and connected to the fuselage at its inboard hinge. Small fragments of debris were observed in the snow continuing about 250 ft above the main wreckage. Lockheed Martin Flight Services reported that no records were located indicating that the airplane's registration number was used to request a weather briefing, either by phone or through any approved DUAT vendors during the 3-day period leading up to the accident. The National Weather Service (NWS) Surface Analysis Chart for 1200 MDT depicted a low pressure system with a central pressure of 995-hectopascals (hPa) over southwestern Wyoming along a frontal wave with a warm front extending eastward across southern Wyoming. Further north, a cold front was depicted surging out of Canada into Montana. The accident site was located between these two systems in an area of light northerly wind, with temperatures in the mid 40-degree Fahrenheit (F) range, with tempera