Flight Information
The commercial certificated pilot was operating a VFR scheduled commuter flight with six passengers between remote villages. Before departure, the pilot contacted the destination airport's village agent via radio and received a weather report indicating an 800-foot overcast ceiling and visibility of 5 miles.
Accident Narrative
After departure, the pilot proceeded toward the destination at an altitude of about 450 feet above ground level. Approximately 10 minutes into the flight, the pilot reported that the horizon became obscured and the area ahead turned white. He noted no precipitation but described the ground and sky as indistinguishable. The pilot initiated a right turn toward the east; about 2 seconds later, the airplane suddenly collided with snow-covered terrain. A passenger reported visibility of about 1 mile under gray skies. The director of operations for the company stated that the weather at the accident scene featured an indefinite ceiling of about 500 feet and visibility of about 2 miles.
Capstone Avionics Equipment
The airplane was equipped with an avionics package provided by the FAA's Capstone Program, a joint industry/FAA demonstration program. The package included GPS avionics, weather and traffic information via automatic dependent surveillance-broadcast (ADS-B), traffic information service-broadcast (TIS-B), and terrain information on a multifunction display (MFD). The terrain display mode provides color shading depicting terrain relative to the aircraft: black (2,000 feet below), green (between 2,000 and 700 feet below), yellow (between 700 and 300 feet below), and red (at or within 300 feet). Accurate terrain depiction requires manual entry of barometric pressure into the MFD, as the Capstone equipment does not receive barometric pressure from the aircraft's altimeter. The map mode does not provide terrain awareness information.
During an interview, the pilot stated that he selected the moving map display with a five-mile scale. He did not observe any warning flags on the MFD and did not manually enter barometric pressure data. The pilot reported that he routinely used his own personal GPS receiver with a color moving map display, which he installed on the glare shield. He noted that because terrain in Western Alaska is usually flat, he routinely used the Capstone map mode with the GPS "go to" function for each leg, rather than the terrain mode.