On October 26, 1997, about 1430 Alaska standard time, a tundra tire equipped Piper PA-12 airplane, N4380M, sustained substantial damage while landing at an off airport site about 20 miles south of Anchorage, Alaska. The Private certificated pilot and the two passengers aboard were not injured. The local, 14 CFR Part 91 flight operated in visual meteorological conditions without a flight plan. The flight departed the private, Sky Harbor airstrip, located in south Anchorage, about 1330. The purpose of the flight was to hunt rabbits, with an eventual return to the Sky Harbor airstrip. During a telephone conversation with the NTSB investigator-in-charge on October 27, 1997, the pilot related he was landing the airplane on ice and snow covered terrain. He said the airplane is equipped with over-sized, 32 inch tundra tires. After touchdown in a tidal zone, the main landing gear wheels broke through an area of thin ice, and into a depression, causing the airplane to decelerate rapidly, and then slowly nose over. The pilot reported damage to the lift struts on the right wing, and wrinkles in the tail section near the vertical stabilizer.