On August 20, 2009, about 2020 Pacific daylight time, a tailwheel equipped Piper PA-22-150, N6038D, sustained substantial damage subsequent to a main landing gear collapse during landing at Tacoma-Narrows Airport, Tacoma, Washington. The student pilot, the sole occupant of the airplane, was not injured. The airplane was registered to the pilot and operated as a personal flight under the provisions of 14 Code of Federal Regulations (CFR) Part 91. The flight departed Paine Field, Everett, Washington, about 1915 with a planned destination of Tacoma. Visual meteorological conditions prevailed, and no flight plan had been filed. In a written report submitted to the National Transportation Safety Board, the pilot reported that during a crosswind landing the right main landing gear strut collapsed. He added that shortly after the "right wing low" wheel landing, he heard the right "gear leg pop." The pilot stated that the winds were from 210 degrees at 8-12 knots and he was landing on runway 17. The airplane sustained substantial damage to the gear support structure and associated gearbox. The forward right landing gear strut attachment fitting was removed from the gear assembly and forwarded to the NTSB Materials Laboratory in Washington, DC, for examination. A Safety Board Senior Metallurgist examined the fitting and reported that the fracture faces displayed features and deformations consistent with overstress separations. The metallurgist reported that no indications of preexisting cracking or corrosion were detected. The Materials Laboratory Factual Report is included in the public docket for this accident. The pilot reported no mechanical anomalies with the airplanes flight control systems prior to the accident.