Marion 8750 "Slide In" Click on any picture for a full size image
Just as in the real surface mines.. the highwall is a constant danger. One wrong move can spell disaster.
It looks like the slide started while the drag was swinging.
The combination of the weight of the machine, and the momentum of the swing, carried the drag into the pit.
Now resting at the bottom of the highwall, it's going to take a lot of work to get back out.