On April 13, 2003, about 1830 Alaska daylight time, a tundra tire-equipped Piper PA-18 airplane, N339T, sustained substantial damage when it nosed over during a precautionary landing at the Summit Airstrip, located about 6 miles southwest of Cantwell, Alaska. The airplane was being operated as a visual flight rules (VFR) cross country personal flight under Title 14, CFR Part 91, when the accident occurred. The solo private pilot was not injured. The flight originated about 1730 from the Fairbanks International Airport, Fairbanks, Alaska, and was en route to Merrill Field, Anchorage, Alaska. Visual meteorological conditions prevailed, and no flight plan was filed. During a telephone conversation with the National Transportation Safety Board investigator-in-charge on April 14, the pilot reported that as the flight progressed through an area of mountainous terrain, he encountered low ceilings, reduced visibility, and light freezing rain. He said that he noticed a light accumulation of rime ice on the leading edge of the airplane's wing, so he elected to land at the Summit Airstrip and wait for better weather. He said that while landing on runway 21, the main wheels contacted deep snow on the runway, and the airplane nosed over. The airplane sustained substantial damage to the wings, both wing lift struts, and rudder assembly. According to the current Alaska Supplement, the Summit Airstrip is not maintained. The pilot noted that there were no preaccident mechanical anomalies with the airplane.