On March 24, 1998, approximately 0930 mountain standard time, a Piper PA-22, N1770A, ground looped while practicing landings at Glacier Park International Airport, Kalispell, Montana. The airplane's main landing gear collapsed and its right wing was substantially damaged in the ground loop, and the private pilot-in-command and one passenger were uninjured. Visual meteorological conditions prevailed for the local 14 CFR 91 flight out of Glacier Park International, and no flight plan had been filed. The airplane, which was originally manufactured with tricycle landing gear, had been converted to a tailwheel landing gear configuration in accordance with Univair's FAA Supplemental Type Certificate (STC) number SA45RM. The airplane also had a Crosswinds short takeoff and landing (STOL) modification installed (FAA STC number SA545AL.). The pilot reported that during a crosswind landing on runway 20, he did not keep full left aileron in. He stated that when he relaxed the wheel input, the wind picked up his left wing, at which point the aircraft's right main landing gear folded and the right wing and propeller struck the ground. The pilot reported that no mechanical failure or malfunction was involved in the accident. Winds at Glacier Park International at 0856 were reported by the airport's automated surface observation system (ASOS) as being from 150 degrees at 7 knots, and were reported as being from 130 degrees at 12 knots at 0956. Runway 20 is an 8,000 by 150 foot asphalt and porous friction coated runway.