WPR15FA247

The non-instrument-rated pilot's decision to conduct a cross-country flight over a mountain range in dark night conditions with limited night flight experience, which resulted in a collision with mountainous terrain.

The non-instrument-rated pilot notified his wife at 2211 that he would be departing the airport momentarily. The direct route to the destination of the dark night cross-country flight crossed a mountain range with elevations over 7,200 ft. The following morning, an emergency locator transmitter signal was detected, and the wreckage was subsequently located in the mountains at an elevation of about 5,000 ft along the direct route of flight. The wreckage pattern and ground scars indicated that the airplane impacted a rock formation on the face of a mountain during a steep right turn. An examination of the airframe and engine did not reveal any preimpact mechanical malfunctions or anomalies that would have precluded normal operation. Although the pilot had accumulated some experience crossing the mountain range, he had never completed this flight in nighttime conditions, and he had only 3.8 hours of night flight experience. The pilot's wife reported that she had made the flight several times with the pilot, and he would typically fly over the mountain range unless the clouds were low, in which case he would take a longer route to avoid the mountains. The departure airport was reporting an overcast cloud layer that was about 8,000 ft mean sea level. Further, a witness at the destination airport reported that the sky condition was "pitch black," which was likely the result of a partially illuminated moon blocked by the overcast layer. In addition, mountain obscuration due to smoke and haze was present at the time of the accident, which would have further decreased the pilot's ability to recognize obstructions. As stated in a January 2008 National Transportation Safety Board safety alert, Controlled Flight Into Terrain in Visual Conditions, "darkness may render visual avoidance of high terrain nearly impossible," and "the absence of ground lights may result in loss of horizon reference." It is likely that the airplane collided with terrain because the pilot could not see and avoid the surrounding terrain given the dark night conditions and mountain obscuration. Pilot spatial disorientation may also have occurred due to multiple risk factors including the pilot's lack of night flight proficiency and his absence of mountain flying experience in dark night conditions. Because the airplane was in a steep turn, it could not be determined whether the pilot was trying to avoid terrain that he saw at the last minute or if he was disoriented and inadvertently banked the airplane.

An autopsy was performed on the pilot by the Montana Department of Justice, Forensic Science Division. The autopsy report listed the pilot/owner's cause of death as "multiple blunt force injuries." Forensic toxicology testing was performed on specimens of the pilot by the FAA Bioaeronautical Science Research Laboratory (CAMI), Oklahoma City, Oklahoma, which did not detect any ethanol in the pilot's muscle or drugs in the pilot's urine. According to an NTSB Meteorological study, the 2253 recorded weather observation at HLN included winds from 250 degrees at 7 knots, visibility 4 statute miles, haze, an overcast cloud layer at 4,100 feet above ground level (agl), temperature 22 degrees C, dew point 5 degrees C, and an altimeter setting of 29.86 inches of mercury. A Terminal Aerodrome Forecast was issued for HLN at 1908. The field weather forecast for the accident time included visibility of 4 statute miles, haze, and scattered clouds at 4,000 feet agl. An Area Forecast was issued at 2045 by the Aviation Weather Center in Kansas City, Missouri. The narrative forecasted a broken smoke layer at 8,000 feet and occasionally visibility between 3-5 statute miles in smoke and haze. The National Oceanic and Atmospheric Administration publishes a Smoke Text Product, which is a narrative used to describe significant areas of smoke associated with active fires. A Smoke Text Product was issued on the day of the accident that reported heavy smoke over parts of Oregon, Washington, Idaho, and Montana, forecast for that evening. The report described moderate density smoke farther east into Central Montana. An Airmen's Meteorological Information (AIRMET) advisory was issued as 2045 for mountain obscuration due to smoke and haze at the time of the accident in a region inclusive of the accident site. The United States Naval Observatory, Astronomical Applications Department for Townsend recorded the moon phase as a waxing crescent Moon with 22% of the Moon's visible disk illuminated. The recorded Moonset for Townsend was 2243. A witness reported the visibility at 76S on the night of the accident was approximately 2 statute miles, and the sky was "pitch black." According to Lockheed Martin Flight Services, the pilot did not file a flight plan or request a weather briefing through them or DUATS. A review of the pilot's logbook revealed that he had amassed a total of 280 flight hours at the time of the accident; about 277 of which were in the accident airplane make and model. The pilot had accrued a total of 3.8 hours of total night flight experience; 3 hours of which were completed with an instructor in October 2013, and 0.8 hours were completed over two separate flights without an instructor. The pilot's first night flight without his instructor took place in December 2014 over 0.4 flight hours. He recorded another night flight about 1 month before the accident, during which time he accumulated 0.4 flight hours. The logbook indicated that both flights consisted of 3-4 landings in the airport traffic pattern. According to the pilot's flight instructor, they completed one instructional cross country night flight from Helena to Bozeman. The second instructional night flight consisted of 12 landings at a local airport and did not include any cross-country flight time. The last entry in the logbook showed that the pilot had flown from 7S6 to HLN on August 19, 2015. Flight Training According to the pilot's flight instructor, the pilot began taking flight lessons from him in April 2013 when the instructor was employed by a flight school at HLN. The pilot received instruction in a Cessna 172M model airplane until he purchased the accident airplane later that year. In September 2014, his flight instructor endorsed him to fly solo to commute between 7S6 and HLN. The instructor stated that the pilot's upset recovery abilities and aeronautical decision making were "typical of someone starting in their late 50's." Private Pilot Examination Records furnished by the Federal Aviation Administration (FAA) indicated that the pilot was unsuccessful during his initial private pilot check ride. According to the designated pilot examiner who administered the check ride, the pilot did not demonstrate adequate pilotage during the examination. The pilot deviated from his assigned course by approximately 7 nautical miles, and was unable to identify multiple terrain features. The pilot subsequently completed two instructional flights that included navigation practice to prepare for the follow-up examination to his private pilot check ride. 72-Hour History A follow-up interview with the pilot's wife was used to construct a 72-hour history of the pilot's activities. On Sunday, August 16, 2015, the pilot attended a church service, and completed some activities around the house. During the following 2 days, the pilot attended gatherings at a local café for coffee, and performed some work within the community. The pilot's wife observed no abnormalities in the pilot's behavior or sleep patterns on the day of the accident and the 3 days that preceded it. The pilot's wife reported that she had flown with him between 7S6 and HLN about four times. During these flights, they would typically fly over the mountain range; however, if the clouds were "too low," they would circumvent the mountain. The airplane impacted an area of mountainous terrain that was located on the rising face of a ridge at a terrain elevation of 5,046 feet. All four corners of the airplane were accounted for at the accident site. A debris path that measured about 100 feet long by 80 feet wide was oriented on a 351-degree magnetic heading. The initial impact point (IIP) was identified by a broken green aircraft position light and silver colored signatures that were vertically oriented, and spanned approximately 13 feet in length on a rock face. The airplane main wreckage, comprised of the cockpit, fuselage, and empennage, was located about 70 feet beyond the IIP. A local sheriff detected an odor at the accident site that resembled fuel. Airframe The outboard section of the right wing was located in the debris path about 30 feet below the initial impact point. A piece of the inboard section of the right wing was identified by the right wing strut, and was located about 15 feet from the main wreckage. The leading edge of the wing was compressed into alternating ridges and grooves that resembled corrugated metal. The right wing fuel tank was breached, and void of fuel. Both the flap bell crank and jackscrew had separated from the right wing, and were found in the energy path about 30 feet from the main wreckage. The flap jackscrew measured 2.9", consistent with a 10-degree flap deployment. The left wing came to rest a few feet from the main wreckage, and was co-located with the engine. Several portions of skin were pulled back away from the wing, which revealed a breached left wing fuel tank that was void of fuel. The rudder, elevator trim, and elevator cables were traced from the cockpit to each control surface. Both aileron cables had separated at the wing roots; however, the fracture surfaces exhibited signatures consistent with tensile overload. The empennage was co-located with the main wreckage, and remained attached to the tail cone by a piece of airframe skin. The vertical stabilizer and rudder assembly were connected, but damaged by the impact. Both elevators remained attached to the horizontal stabilizers; however, the right and left elevator torque tubes had separated in tensile overload. The elevator trim tab measured 1.15", indicative of a 5-degree tab down position. The fuel selector handle had separated and exposed the selector pin, which rotated successfully to each detent. Air was directed through the unit as the selector was moved, which confirmed continuity through the left, right, and both positions of the selector. The fuel strainer bowl was found in the debris