N6184FCessna 182P · 1975

On October 8, 2015, at 0826 Pacific daylight time, a Cessna 182P airplane, N6184F, collided with mountainous terrain about 3.5 miles northeast of Hope, Idaho. The private pilot and both the commercial pilot-rated passengers were fatally injured. The airplane impacted large pine trees near a mountain ridge line and was destroyed by a post-crash fire. The airplane was registered to the private pilot and operated under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed for the flight, and a flight plan had not been filed. The flight originated at the Bird Nr 2 air strip (elevation 2,192 feet msl), Sagle, Idaho, at 0816, and was destined for Minot, ND.

The Air Force Rescue Coordination Center (AFRCC) reported that at 0823 they received reports of a single emergency locator transmitter ping in the vicinity northeast of Hope. About 6 hours later, a helicopter located the wreckage just below a ridgeline saddle on the mountain slope northeast of Hope, at an elevation of 5,226 feet mean sea level (msl). The airplane had first impacted numerous tree tops then collided with terrain about 156 feet later, along a 046-degree magnetic bearing line. There was a post-crash fire that destroyed the airplane cabin.

Radar data depicts a target over Hope, ID, at 0820, at 3,600 feet, with the track proceeding to the northeast, heading directly into rising mountainous terrain. A total of 16 radar returns were identified along this track. The final radar return was at 0823, 4,900 feet, in the vicinity of the accident site.

Family members reported that the intended route of flight was to depart Sagle, proceed to Minot, then to Maine, and then proceed along the east coast of the US, with a final destination of Gainesville, Florida. The flight was scheduled to depart on Wednesday, October 7, but was delayed due to poor weather conditions. Just before the airplane departed, the pilot-rated passenger told the ranch foreman that they were heading to Minot, but because of the weather they were probably going to try to go south. The ranch foreman also stated that on Tuesday he had fueled the airplane to maximum capacity.

The pilot, age 59, held a private pilot certificate with a single-engine land rating, issued May 23, 2013, and a third-class airman medical certificate issued January 22, 2015, with the limitation that she must have glasses available for near vision. The pilot's logbook was not recovered for examination. On the pilot's January 22, 2015, medical certificate application, she reported her total flight time was 250 hours, with 60 hours flown in the previous six months.

The pilot-rated passenger (copilot), age 80, held a commercial pilot certificate with ratings for single-engine and multiengine airplane land, and instrument airplane, she also held a flight instructor certificate with ratings for airplane single-engine, instrument airplane, and ground instructor (basic). She held a second-class airman medical certificate issued on October 30, 2013, with the limitation that she wear corrective lenses. Her pilot logbook was not recovered for examination. On her October 30, 2013, medical application she reported her total flight time was 3,500 hours, however, on her 2012 medical certificate application she reported 13,000 hours of flight time.

The pilot-rated passenger in a rear seat, age 84, held a commercial pilot certificate with ratings for single-engine land, and instrument-airplane. He held a third-class medical certificate issued October 31, 2013, with the limitation that he must wear corrective lenses. His pilot logbook was not recovered for examination. On his October 31, 2013, medical application he reported his total flight time was 2,000 hours, however, on his 2012 medical certificate application he reported 7,030 hours of flight time.

A photo of the airplane was taken immediately prior to the departure. The photo showed the private pilot in the left front seat, the CFI in the right front seat, and a male passenger in one of the rear seats.

The four-seat, high-wing, fixed-gear, airplane, serial number 18264118, was manufactured in 1975. It was powered by a Continental Motors IO-470-F27B, 260-hp engine, and equipped with a McCauley constant speed propeller model 2A34C66-NP. Airplane maintenance records were not located, and are believed to have been onboard the airplane. The records are presumed to have been destroyed in the post-crash fire. The mechanic who performed the most recent maintenance stated that he performed an annual inspection on September 27, 2015, and provided an invoice of the work.

The nearest weather reporting station was the Sand Point Airport (KSZT), elevation 2,131 feet msl, located 15 miles west of the accident location, and operates a AWOS-3 (automated weather observation system). On October 8, at 0815, the KSZT AWOS-3 observation reported calm wind, an overcast layer at 2,800 feet above ground level (agl), 7 statute miles visibility, temperature of 11 degrees C and dew point of 11 degrees C, and altimeter setting 30.29 inHg. The 0835 observation recorded an overcast layer at 2,800 feet agl, 10 statute miles visibility, temperature 12 C, dew point 12 C, and altimeter 30.29 inHg.

WSR-88D Level-II weather radar imagery from Spokane, Washington (KOTX), KOTX was located approximately 66 miles southwest of the accident site at an elevation of about 2,400 feet. Assuming standard refraction and considering the 0.95° beam width for the WSR-88D radar beam, the KOTX 0.457° tilt would have "seen" altitudes between about 5,200 and 11,800 feet above msl at the accident location. KOTX did not depict any pertinent areas of reflectivity during the time of the accident.

A North American Mesoscale (NAM) model sounding for the accident location at 0800 PDT was retrieved from the National Oceanic and Atmospheric Administration's (NOAA) Air Resources Laboratory. The wind between the surface and about 8,000 feet was less than 10 knots and veered from a south surface wind to a westerly wind near 8,000 feet. Above this level through about 10,000 feet, the wind was from the west at near 10 knots. Relative humidity was 90 percent or greater from the surface to about 6,500 feet. The freezing level was identified as 11,375 feet. No significant areas of turbulence were noted by the Rawinsonde Observation Program (RAOB).

The satellite GOES-15 visible imagery identified cloudy conditions in the accident region, with infrared cloud-top temperatures varying between approximately -6°C and -24°C in the vicinity of the accident site. When considering the NAM model sounding, -6°C and -24°C corresponded to cloud heights of approximately 15,300 and 24,000 feet, respectively.

The Aviation Section of the Area Forecast discussed the weather conditions as follows for the 0800 PDT Terminal Area Forecast (TAF): the surface layer is well saturated this morning and with up-sloping flow into the higher terrain of northern Washington and Idaho expect areas of stratus and fog for Spokane, Felts Field, and Lewiston (KGEG/KSFF/KLWS) with a mix of IFR and MVFR conditions through the morning. Surface winds are expected to come around to the ESE between 0500 -0800. This will push the low level out into the basin with drying at KGEG/KSFF/KLWS between 1100 -1300 with VFR conditions expected for all TAF after 1300.

AIRMET's (Airman's Meteorological Information) for IFR and mountain obscuration were active in the vicinity of the accident for altitudes below 10,000 feet.

A video taken of the accident aircraft's departure from the Bird Nr 2 air strip is included in the NTSB docket for this accident. The video shows the accident airplane departing to the south. Ceiling and prevailing visibility cannot be measured definitively from this video (and only about half of the horizon circle is visible), however terrain and trees immediately surrounding the air strip are clearly visible. Some low cloud (or smoke) is evident in the region, and distant terrain to the south is almost completely obscured by cloud (a comparison was made with a clear day image of the distant terrain from the air strip). Ceiling of unknown height appears broken, with "blue sky" visible. Lighting is consistent with a cloudy or overcast day-time environment.

The certified flight instructor (CFI, pilot-rated passenger) contacted Prescott Flight Service on the afternoon of October 7, 2015, at 1343, requesting a weather briefing for a flight from Sandpoint, ID, to Minot, ND, departing within the next hour. The briefer described AIRMET Sierra for IFR conditions and mountain obscuration at the higher elevation terrain, VFR flight not recommended, and conditions extend from the departure location all the way through the mountains. At that point the CFI stopped the briefing and asked for the next day's outlook. The briefer stated that conditions would remain similar to current conditions but the amount of precipitation would decrease by early morning. The CFI stated that she was not going to fly in the mountains with the type of conditions described. The briefer continued to say that it would be a couple of days before conditions changed significantly. The CFI then asked if conditions would be better if they flew south then east, and the briefer stated that the AIRMET extended to central Idaho in every direction. Prescott Flight Service had no record of additional weather briefings for the accident airplane.

The wreckage was located by a local helicopter crew about 6 hours after the airplane departed ID19, Sagle, ID. The wreckage was located 7 miles northeast of the departure airport on the western slope at the end of a box canyon that feeds the Strong Creek and is oriented southwest-northeast. The terrain is populated by 80-foot mature pine trees, underbrush, and the ground consists of shale rock. The wreckage was located on the western face of a ridge line that dips into a saddle 0.5 miles northwest of Round Top Mountain at an elevation of 5,226 feet, approximately 25 feet below the ridgeline. The initial point of impact was identified by freshly broken pine tree tops and two fragments of the right elevator 156 feet from the main wreckage. The directional bearing between the initial point of impact and the main wreckage was 046° magnetic. The airplane cabin, and both wings were subjected to a post-impact fire which destroyed all cockpit instruments, furnishings, and personal items.

On-scene examination of the airframe revealed that both wings and the left elevator had been separated from the airframe during impact with the trees. Control continuity was established for the ailerons left and right quadrants through multiple overload separations of the control cables. The elevator cable was examined from end to end and had an overload separation one foot from the forward termination. The rudder control cable was continuous from end to end and attached to the rudder bar in the cockpit and rudder horn on the rudder. The elevator trim measured 1.4 inches which equates to 5 degrees up tab setting. The flap jack screw was observed in the fully retracted position, corresponding to full flap retraction.

The cockpit was completely destroyed by fire. No instruments were readable, no avionics, or engine instruments were recognizable, except for the wet compass. The windscreen had separated from the cabin intact and was off to the side of the wreckage. The engine controls (prop, mixture, throttle) handles were all fully pushed into their stops. The control cables passed through the firewall and forward to the engine.

The engine accessory section had been exposed to extreme heat and fire. Forward of the baffle between the accessory section and the engine block was discolored black, both magnetos were attached to their respective mounting pads, magnetos and the spark plug leads exhibited heat damage. The fuel distribution valve was discolored black; when disassembled the diaphragm was undamaged and the filter screen was clear of visible debris. Spark plugs were removed, the electrodes were dark grey in color with no mechanical damage evident, consistent with normal wear signatures. There were no visible oil leaks from any of the cylinder covers. The intake and exhaust manifolds appeared undamaged.

Attached to the engine crankshaft flange was a two-bladed constant-speed propeller. The spinner had a dent on one side but remained attached to the hub. Blade 1 exhibited no leading edge gouges or chordwise scratches. Torsional twisting back toward the blade face was evident along the length of the blade. Blade 2 exhibited no leading edge gouges or chordwise scratches. The blade was bent aft approximately 50 degrees at mid-span.

On November 10, 2015, the engine was examined by a technical representative of the engine manufacturer under the oversight of an FAA Inspector. No pre-accident anomalies were identified with the engine and engine-related systems that would have prevented the engine's ability to produce full, rated power.

The wreckage examination identified no anomalies or malfunctions of the airplane or engine that would have precluded normal operation.

The pilot was not recovered from the wreckage and her remains were presumed to have been completely consumed by the post-crash fire.

An autopsy was performed on the copilot on October 12, 2015, by the Spokane County Medical Examiner.

The FAA's Civil Aerospace Medical Institute performed forensic toxicology on specimen from the copilot with negative results for ethanol or listed drugs.

Family members of the copilot were able to login into the copilot's ForeFlight account, and using a surrogate tablet computer accessed the most recent flight plan activity. The ForeFlight application flight plan page showed the route of flight as ID19 (Bird Nr2 airport) to KMOT (Minot, ND) as the first leg of the flight. The following destination were shown in order, KMOT to KDVL (Devils Lake, ND), KERY (Newberry, MI), KMCD (Mackinac Island, MI), KHBI (Asheboro, NC), KMHT (Manchester, NH), MHKY (Hickory, NC), and KGNV (Gainsville, FL). The planned cruising altitude was 8,500 feet, and airspeed was 137 kts. The initial direction of flight was 99 degrees magnetic.