jomoco
Tree Freak
Well, as you can see here, that's not what they did when they lifted the log out....But those of us who guessed its weight were way way off, it weighed 12,100 lb!! So, the main screw up was not estimating the wood weights before the job started. I can see in the enclosed photo that the piece is much larger than earlier photos made it appear.
http://www.pressdemocrat.com/article/20091125/ARTICLES/911259959
Now, vet, I still don't agree with your method for that piece of wood, given its asymetricity, and the fact that it wasn't vertical, and had that arm off to the side. However, by slowly picking it to vertical, as I described, the main advantage is the load moves closer to the centerpin, and there's no shock loading at all. Having two chokers near the top, opposed, would prolly be fine, but it would still need to be cut the way I said...or perhaps better, with a face cut first, then, yes, wedges if needed, to bring to to as close to plumb as possible.....IMO of course..
And, all this kibbitzing is moot, as we now know they were picking twice what they were rated for. TWICE!!!!!
Nice detective work RB!
Maybe this incident will eventually lead to arborists and CO's using a green wood weight calculator on the job in real time?
I did a bit of detective work myself and found that a full set of CW's for a GMK 5160 weighs over 100K lbs!
jomoco