On June 1, 1998, at 1500 mountain daylight time, a Cessna 170B, N1896C, was substantially damaged during landing roll near Los Alamos, New Mexico. The private pilot, the sole occupant aboard, was not injured. The airplane was registered jointly to two individuals and was being operated by the pilot under Title 14 CFR Part 91. Visual meteorological conditions prevailed for the personal flight which originated in Espanola, New Mexico, 15 minutes before the accident. No flight plan had been filed. According to the pilot's accident report and a telephone conversation with the Investigator-In-Charge, the pilot stated that he was performing a wheel landing on runway 27 (5,500 ft. X 75 ft., elevation 7,171 feet), which is located on top a mesa with trees lining the south side. He stated that he requested an airport advisory which gave the wind at S-SE for 10 knots with gusts to 20 knots. The pilot stated that when the airplane touched down, it began to "weather vain," and it exited the runway to the left striking a ditch and fence. Both wings were substantially damaged as well as the landing gear and propeller. At the time of the accident, density altitude was 10,459 feet.