On June 18, 2002, about 1700 Alaska daylight time, a tundra tire equipped Wagabond Traveler, N36GM, sustained substantial damage during taxi to parking on a sandbar in the Chulitna River, about 4 miles northwest of the Talkeetna Airport, Talkeetna, Alaska. The airplane was being operated as a visual flight rules (VFR) personal flight under Title 14, CFR Part 91, when the accident occurred. The private pilot and his one passenger were not injured. The flight was intended to be a local flight, and no flight plan was filed. The flight departed the Talkeetna airport about 1500. During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC) on June 20, the pilot said he landed on a large sandbar in the Chulitna river. He said he was taxiing to parking on the sandbar, when the main landing gear dropped into a deep, muddy wash, at the same time a gust of wind picked up the tail of the airplane, causing it to nose over. During the nose-over, the vertical stabilizer was crushed and the wing lift-struts were bent. The composite propeller was shattered. The pilot said he and his passenger were able turn the airplane over onto its wheels. He said he used the emergency locator transmitter (ELT) to summon help. In a written statement the pilot said he was carrying too much forward speed/ momentum while taxiing on the sandbar. He said a gusting tailwind during the taxi also contributed to the airplane nosing over.