Jackie previously posted:
"Or maybe having "back-up rigging" for something so big??? I'm just sayin'...
I don't know rigging - but I would have wanted more chains for that."
Most rigging equipment including the chains and straps and such is typically supposed to have at least a 2 to 1 safety factor, and most riggers I know like to have a 5 to 1 safety factor. 2 to 1 meaning twice the load carrying capability and 5 to 1 meaning 5 times the load carrying capacity.
I dead fairly regularly with this stuff at work (as does you hubby I'm sure) with much lighter loads but similar idea, and its crazy how weight can transfer. A guy put a load sensor on a bunch of rigging pick points that were connected, and a bumping one point up an inch raised the load on that point by almost double. When you are lifting stuff that heavy in a environment that is constantly shifting, it can take just a slight breeze or a the boat tipping a little bit to shift all the weight to one point (which is likely what happened in this) and stuff fails.
Also, have a safety back up is good but usually only affords you a few extra seconds to think and get out of the way. If that chain broke, any chain that would have caught would have been heavily shock loaded and would probably have snapped instantly. I'm guess that either the chain wasn't strong enough, or there was a defect of some sort that lowered the strength that no one saw. All I know is that those guys are lucky there was no major damage and that one one was hurt, as the liability lawsuits involved with that stuff can be pretty heavy and life altering. Guys who are good at working with heavy lifting and rigging are worth every dime of what they charge. Bad stuff happens that you don't expect sometimes, but the really good guys have the gut feelings and alarm bells that keep them and their surroundings safe. The ones who don't can be downright scary though, and I either run away or get them off site as fast as I can and replace them with competent people. Fortunately the scary riggers don't get called to work very often, so its pretty rare to have to do that.
All of that said, its kind of fun to see big stuff fail sometimes. Its just as cool to see professionals complete the task though, and is much more impressive to me even though it gets less attention.