Abstract: Employees #1 through #4 were part of a crew drilling an oil well at a site northwest of Wynona, OK. They had removed the drill bit and placed it on the oil rig floor, and had put the last stand of 900 lb, 30 ft long drill pipe collars in the pipe rack when the Franks Explorer drilling rig collapsed. Employee #1, the derrickman, was killed. Employee #2, the driller, sustained back injuries and was hospitalized. Employees #3 and #4, both rig hands, suffered minor injuries and were treated and released that same day. The most likely cause of the accident was the load shifting. Subsequent investigation revealed that there was no escape device in the pipe rack, which was approximately 60 ft above the rig floor. Also, the wind gust anchors were not set in the proper location, the anchorage system was not appropriate for the job, and the rig was not properly maintained.