A Rig mast carrier was being transported down an incline, on route to the new location. The Rig mast carrier was supported by the use of four D8 Dozers positioned in series at the rear. Once the rig carrier passed the apex of the descent, the 28mm steel wire rope connecting the first D8 to the carrier parted. The rig continued its descent under the control of the prime mover and rig mast brakes and stopped safely at the bottom of the decline.