WPR18FA095

The noninstrument-rated pilot's continued flight into a region of deteriorating ceiling and visibility conditions, which resulted in controlled flight into terrain event.

The non-instrument rated private pilot intended to fly his single-engine airplane to an airport about 850 nm south of the departure airport. The day before the accident, the pilot and his three passengers departed and subsequently landed about 6 hours later at an intermediate airport about 260 nm short of their ultimate destination. The pilot requested a fuel top-off, and then the group left the airport to overnight in nearby lodging. The accident flight departed the next morning about 0937, and there were no known communications between the airplane and any air traffic control facilities after departure. An overdue aircraft notice was issued that night in response to concerns raised by friends or family members of the occupants. The wreckage was located the following afternoon in flat open terrain about 85 nm south-southwest of the departure airport. All four occupants were fatally injured; occupant watches indicated that the time of the accident was about 1056, or about 79 minutes after takeoff. Ground-based radar captured about 30 minutes of the mid portion of the flight; the final radar return was received about 23 minutes before the accident and depicted the airplane about 35 nm north-northwest of the accident site. The airplane was in a slow descent when the radar data ended, but there was about 2,500 ft between the radar coverage floor and the underlying terrain. The final radar return was at a radar-indicated altitude of 9,200 ft. Calculations using estimated airplane cruise and wind speeds indicated that the airplane could have traveled about 53 nm during the time between the final radar return and the accident; this was about 22 nm more than the straight-line distance between that radar return and the accident site, suggesting that the pilot likely deviated from a direct route to his destination. The debris field indicated that the airplane impacted the ground in a shallow descent with significant horizontal velocity, on a heading of approximately east. Examination of the airframe and engine accounted for all major components, indicated that the engine was producing power, and that the landing gear was retracted at the time of impact. The examination did not reveal evidence of any pre-impact mechanical deficiencies or failures. A weather study revealed the potential for reduced ceilings and/or visibilities, including instrument meteorological conditions, in the area of the accident site around the time of the accident. Cloud bases were likely about 9,500 to 10,000 ft msl, and cloud top heights were about 26,600 ft. The forecast warned of convective snow bands, capable of reducing visibility to less than 1 mile, and lowering ceiling heights to a few hundred feet. Toxicological testing of tissue samples from all four occupants did not reveal the presence of carbon monoxide in any of them. Toxicological testing identified diphenhydramine in tissue samples from the pilot. However, because the tissue sample type did not provide a reliable level of diphenhydramine in the pilot, a reliable determination of whether the pilot was impaired from the use of the sedating medication also could not be determined. Based on the available evidence, it is likely that the pilot was attempting to maneuver the flight through a region of deteriorating ceiling and visibility conditions, during which he descended the airplane to an altitude where the airplane inadvertently collided with the underlying terrain.

Pilot The Utah Department of Health Office of the Medical Examiner, Taylorsville, Utah, conducted the autopsy on the pilot. The cause of death was "multiple injuries" due to impact. Examination for pre-existing or contributing medical conditions was not possible due to the injury level. Toxicology testing by NMS Labs for the Utah medical examiner did not reveal the presence of carbon monoxide, alcohol, or any tested-for drugs, except caffeine. Toxicology testing on pilot tissue samples was also conducted by the FAA Forensic Sciences Laboratory. No carbon monoxide or cyanide testing was performed by this laboratory. Normally, central blood is needed to establish medication levels that can be used to estimate impairment, but only pilot's muscle tissue was available. No ethanol was detected in the pilot muscle tissue. No tested-for drugs, except Diphenhydramine, were detected in the pilot's muscle tissue. The detected level was below the FAA threshold for reporting the value of the quantity detected. Diphenhydramine (generic and several brand name products such as Benadryl®, Sominex®, Advil® PM) is an over-the-counter antihistamine used to treat allergic conditions, and is helpful as a sleep aid. This medication could impair mental and/or physical ability required for the performance of tasks such as flying, and the FAA recommends waiting at least 60 hours after the last dose before performing safety-related duties. Passengers Toxicology testing on samples from the three passengers was also conducted by the FAA Forensic Sciences Laboratory. Blood samples from all three individuals tested negative for carbon monoxide. Pilot Briefing Information According to Leidos Flight Service, the pilot did not contact either Leidos or DUATS on the accident day. According to a representative of ForeFlight, a pilot information and flight planning software company, no weather briefings were requested for the airplane using ForeFlight Mobile before the accident flight, or for any flights immediately preceding the accident flight. It also "appeared" that the accident pilot did not sign in to and use his device on ForeFlight Mobile to view any weather imagery before the accident flight. As of the date of the accident, the ForeFlight system did not have the ability to record whether the pilot viewed any "live" weather overlays, such as radar or satellite imagery, over the map view before the flight. The ForeFlight system also did not have the ability record whether the pilot viewed any individual METARs, TAFs or "MOS" (Model Output Statistics) forecasts. Weather Observations An Automated Weather Observing System (AWOS) was located at Blanding Municipal Airport (BDG), Blanding, Utah, about 19 nm southwest of the accident location at an elevation of 5,870 ft. This station did not have a precipitation discriminator and sky condition was not reported. The 1055 observation included wind from 180° at 8 knots, visibility 10 statute miles, temperature 0°C, dew point -8°C, and an altimeter setting of 30.08 inches of mercury. An Automated Surface Observing System located at Cortez Municipal Airport (CEZ), Cortez, Colorado, about 39 miles southeast of the accident location at an elevation of about 5,920 ft, was the closest reporting official ceilometer to the accident site. The 1053 CEZ observation reported wind from 230° at 11 knots with gusts to 18 knots, visibility 10 statute miles, a broken cloud ceiling at 4,800 ft above ground level (agl), overcast clouds at 6,500 ft agl, temperature 1°C, dew point -10°C, and an altimeter setting of 30.03 inches of mercury. There were no publicly-disseminated pilot reports made within about 40 nm and 2 hours of the accident location for altitudes below 15,000 ft. An atmospheric sounding valid for the accident time and location indicated a surface wind from the south-southwest of about 10 knots. Above this level, the wind veered to the west-southwest and increased steadily in magnitude to about 30 knots about 15,000 ft. Between about 9,000 and 13,000 ft, the relative humidity was between 88 and 93 percent. The freezing level was below the surface. A risk of light mixed, and rime icing was identified between about 9,000 and 13,000 ft. No layers of potential significant turbulence were identified below 20,000 ft. Satellite visible and infrared imagery near the time of the accident depicted cloudy skies over the accident region with the infrared data indicating cloud top heights about 26,600 ft. Analysis of National Weather Service (NWS) forecast and weather model data indicated that the cloud bases in the region of the accident site (elevation 6,850 ft) were likely about 9,500 to 10,000 ft msl. The local NWS reported that it faced, "A challenging aviation forecast on Thursday [February 22] afternoon with several instances of convective snow bands producing highly variable conditions from the Colorado border eastward. These bands have been capable of dropping visibility to under a mile and lowering ceiling heights to LIFR [low IFR] levels, however only for short periods of time." The pilot held a Transport Canada (TC) private pilot license. According to a TC explanatory letter, the pilot's "license is endorsed with a blanket type rating for All Single Pilot Non-High-Performance Single Engine Land Aeroplanes." Subsequent communication from TC indicated that a high-performance airplane was defined as "an aeroplane that is specified in the minimum flight crew document as requiring only one pilot and that has a maximum speed (Vne) of 250 KIAS or greater or a stall speed (Vso) of 80 KIAS or greater." The pilot did not hold an instrument rating, and his license bore the restriction, "Valid Daylight Only," which applied in both Canada and the US. Based on TC and FAA information, regarding the TC certificate restriction, the accident airplane was not considered "high-performance" and therefore did not apply, but the daylight restriction applied to the pilot whether he was flying in Canada or the US. Flight time records indicated that, as of February 9, 2018, the pilot had about 597 total hours of flight experience. His most recent TC Category 3 medical certificate was issued in February 2018. The pilot's journey log was recovered in the wreckage. It had separated into a few major portions, and some pages were missing. The earliest entry was dated February 13, 1983, and the most recent was dated February 9, 2018. The first entry that cited the accident airplane was dated June 24, 2014. A review of the entries in the log indicated that the pilot had accumulated about 346 hours in the accident airplane. Due to the damage and missing pages, his total flight experience could not be determined from the recovered Journey log. General Information The partially snow-covered wreckage was in a field about 10 nm southeast of Monticello, Utah, about 85 nm south-southwest of the accident leg departure airport. Investigative examination of the site was conducted 4 days after the accident. Occupant watches indicated that the time of the accident was about 1056. The debris field was oriented on a magnetic track of about 085° (095° true) and was about 550 ft long. The site elevation was about 6,850 ft msl. The wreckage was highly fragmented. An investigative team mapped the debris field and conducted an initial wreckage examination. All major components of the airplane, including all flight control surfaces, were identified at the scene. No fuel was observed on site. No evidence of any pre-impact mechanical deficiencies that would have precluded continued flight were observed. No evidence of any pre-or postimpact fire was observed. Airframe Information Both wings had fracture-separated from the fuselage. The flap and aileron were fracture-separated from the left wing. The aileron, outboard fuel tank, and wing tip were fracture-separated from the right wing. The right flap remained attached to the wing.