On March 27, 1997, about 1115 Alaska standard time, a ski equipped Piper PA-18 airplane, N4055Z, sustained substantial damage while landing at the Birchwood Airport, Chugiak, Alaska. The solo private pilot was not injured. The 14 CFR Part 91 flight operated in visual meteorological conditions, and no flight plan was filed. The flight originated in south Anchorage, Alaska, at the Flying Crown airport about 1045, and the destination was the Birchwood Airport. The pilot reported he was landing on a snow covered area before the approach end of runway 19. During the landing roll, the right main landing gear leg collapsed, causing substantial damage to the right wing's lift strut. The pilot said he landed on the snow covered area because the airplane was still equipped with skis, and the runway was free of any snow. A witness who observed the landing at the uncontrolled airport, noted the area the pilot landed on was well short of the runway, and consisted of patchy, soft snow.