On September 13, 2013, about 1315 Alaska daylight time, a Cessna U206F airplane, N8316Q, operated by a private individual, was substantially damaged when it collided with mountainous and hilly terrain about 25 miles northeast of Kotzebue, Alaska. The commercial pilot and passenger were seriously injured. The personal flight was conducted under the provisions of 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed for the planned flight to Ralph Wien Memorial Airport, Kotzebue, Alaska. No flight plan was filed for the flight that departed from a remote hunting camp near Kiana, Alaska, about 1300. The pilot stated that the purpose of the accident flight was to get supplies at Kotzebue and return to the hunting camp. Prior to departure, he obtained a pilot report from another pilot that had just flown the route. The pilot report included visibility 25 miles, clouds at 1,400 feet, and a ceiling at 1,800 feet. The accident airplane departed uneventfully and was in cruise flight as it approached the last ridge before Kotzebue. The pilot further stated that the Kotzebue peninsula was visible in the distance with an estimated 500 feet of clearance, between the top of the ridge and the base of the cloud layer. The pilot added that as the airplane neared the ridge, a severe downdraft was encountered along with abrupt entry into instrument meteorological conditions. He stabilized the airplane using cockpit instrumentation; however, the airplane collided with the ridge about 30 to 50 feet below the ridgeline. The pilot also noted that there were no preimpact mechanical malfunctions with the airplane. A handheld GPS was recovered from the airplane and forwarded to the NTSB Vehicle Recorders Laboratory, Washington, DC, for data download. Review of the downloaded data revealed that during the last 6 minutes of flight, the airplane climbed from a GPS altitude of 709 feet to a GPS altitude of 1,955 feet. During the last 1 minute of flight, as the airplane approached the ridge, it climbed from a GPS altitude of 1,562 feet, to a GPS altitude of 1,955 feet. One second later, the airplane descended 6 feet to a GPS altitude of 1,949 feet, followed by a 10-foot descent to 1,939 feet 8 seconds after; however, the groundspeed between those two records decayed from 53 knots to 12 knots, consistent with collision occurring during that time. After learning about reports of a weak emergency locator transmitter signal north of Kotzebue, search and rescue personnel aboard an Army National Guard UH-60L helicopter were dispatched from Nome, Alaska. The two seriously injured occupants remained at the accident site, while pinned in the wreckage, for approximately 28 hours before rescue personnel could reach the accident site. The closest weather reporting facility was at Kotzebue, about 25 miles southwest of the accident site. At 1253, a weather observation was reporting, in part: Wind from 230 degrees at 17 knots; visibility 9 miles in light rain, broken ceiling at 1,900 feet, overcast ceiling at 2,500 feet; temperature 6 degrees C; dew point 3 degrees C; altimeter 29.81 inches Hg. At 1353, a weather observation was reporting, in part: Overcast ceiling at 1,700 feet.