On September 26, 2001, about 1830 central daylight time, a Colonial C-2, N273B, piloted by an airline transport pilot, sustained substantial damage when the landing gear collapsed during landing on runway 20 (2,230 feet by 140 feet, turf) at the Faribault Municipal Airport, Faribault, Minnesota. The 14 CFR Part 91 personal flight was not on a flight plan and was operating in visual meteorological conditions. No injuries were reported. The local flight originated about 1800. A postaccident examination of the airplane revealed that the right main landing gear air-oil shock absorber (oleo) was broken. Further examination revealed that the end cap of the oleo was separated from the outer tube of the oleo. The end cap was held in place by two bolts, 180 degrees apart, inserted radially through the outer tube. The bolts were then threaded into the machined end cap. The holes in the outer tube were elongated and torn out to the end of the tube. Further examination revealed a second set of holes through the outer tube about 90 degrees to the first set of holes. The second set of holes also revealed elongation of the holes. According to the airplane owner, the right oleo was an original part. The left strut had been replaced with a new strut since the airplane was manufactured in 1959. According to the airplane type certificate holder, it is an approved repair procedure to rotate the outer tube of the oleo and drill a second set of holes when elongation of the first set is discovered.