Spats:
Thanks for the video. Watching those kinds of accidents is always interesting and informative. I had watched the video several times and came away with ideas about what had happened. I clicked back to your thread, and it seems that Azcats put my thoughts into words, perfectly. Except, I just thought the load line drum brake had failed. Obviously, if the crane operator fiddled with one of the control sticks this could lead to disaster.
I suspect they intended to walk the Transi-Lift back a few yards as they lowered the dragline boom under somewhat more controlled conditions. They can walk that crane around under load. They can boom out, but they can’t swing, so that’s the only means they have of positioning a load. Riggers live dangerously, don’t they? That’s really interesting work, but they do take us engineers outside our comfort zones at times. Sure it’s over stressed a little, but that’s what FoS are for, and besides it’s only for a short period of time, so what could possibly go wrong?