Abstract: On May 4, 1987, Employee #1, a crane operator, was traveling with a load attached to the crane's main hoist line. The crane load consisted of ICE 26-in. swinging leads, 72-ft-long and weighing 7,920 lb; construction form; a continuous flight auger, 16 in. in diameter, 59 ft long, and weighing 3,127 lb; and a Model 3040 4,500 lb auger drive for a total weight, without the drilling attachment, of 15,547 lb. The crane was traveling between the south side of a hospital and a riverbank, over an area of fill 17.5 ft deep and consisting of brown silty clay with fragments of rock, brick, coal, concrete, and roots. As the crane moved from west to east, a piece of concrete surfaced in front of its right track. The crane operator tried to move over or around the piece of concrete, but the crane kicked back and the engine stalled in reverse configuration, completely reversing all its mechanical power-transmission apparatus. As the crane attempted to maneuver around the piece of concrete, the boom structure and load swung downhill toward the river embankment on Employee #1's right side. After a failed attempt to swing the load back uphill toward the hospital, he tried to lower it. The main hoist drum assembly foot brake was down and in a locked position, but with the mechanical power-transmission apparatus in reverse, the main hoist drum assembly rotated upward rather than downward. Employee #1 tried this maneuver several times until the crane load suddenly stopped because the assembly was in a locked position. This sudden stop created a dynamic (loading) to the crane and caused its uphill track to lift up. The crane overturned, killing employee #1.