On June 24, 2001, at approximately 1200 mountain daylight time, a Piper PA-12, N7850H, was substantially damaged when it collided with terrain near Eagle, Colorado. The private pilot, the sole occupant in the airplane, was not injured. The pilot was operating the airplane under Title 14 CFR Part 91. Visual meteorological conditions prevailed for the personal flight which originated from Boulder Municipal Airport, Boulder, Colorado, at approximately 1030. The pilot did not file a flight plan. According to the pilot's written statement, he was planning to fly "more or less" direct to Castle Peak (approximately 9 miles northeast of Eagle County Regional Airport) to look for landing sites on BLM (Bureau of Land Management) land. He identified a potential landing site at approximately 11,000 feet elevation. He decided he would attempt an approach from the west, uphill. On short final, he "realized that my sink rate was higher than I was comfortable with, and my groundspeed was too high," and he tried to go-around. He applied full power, but was unable to clear the terrain. The airplane was in a 30 degree crab, and the pilot attempted to correct it back to the ground track by adding right rudder. The right main landing gear contacted the ground, and the airplane turned approximately 180 degrees and came to rest in about 100 feet. The landing gear separated from the fuselage, both wings were wrinkled on top, and the cowling was bent. The pilot said that after he exited the airplane, he observed that he had landed with a 20 knot quartering tailwind. He also stated that the ambient air temperature at the crash site was 60 degrees Fahrenheit; the calculated density altitude was 13,418 feet.