Abstract: Employee #1, a logger, believing that the skyline had been slackened, was releasing the support line to the intermediate support tree jack. As he loosened the U-bolts to render the slack through and lower the jack, one of the U-bolts came apart and Employee #1 leaned over to pick up the parts. As he did this, the sklyine began moving toward the tailholt, creating severe downward pressure on the tree jack. The jack support line stripped under Employee #1's arms and around the tree, and the choker bell at the end of the line whipped up and struck him in the face. Employee #1's arms and face were severely injured, and he was admitted to the hospital for treatment.