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LLD
The line you were using sounds a bit short? ... It’s much easier for the riggers to push the section around for final placement when the line is longer… and you don’t have to move the machine around as much...
You can have the sight picture/hook off to one side a skoshe (not a lot more) and they’ll still get the pins or bolts in…Also don’t overestimate the experience/competence level of the riggers as they are a key element of any smooth operation…
Think of the 1:60 rule in a vertical sense…D = Length of longline
At D X 60 (longer-line) You can move around say 4 degrees from the vertical at the helicopter end (due to over controlling or wind etc)
At D X 15 (shorter-line) You can only move around 1 degree from the vertical for the same amount of movement at the hook end. So the control accuracy you need at the helicopter end is much greater with a shorter line.. This is of course predicated on you being comfortable with the longer line and making small smooth corrections and getting the sight picture back over the target zone…
You were working with D X 15 accuracy requirements and it made the job much harder….I hope this makes sense?...Sounds unnecessarily complicated but I can’t think of a better way to explain it…Try to use a longer line at all times, and then when you really need the accuracy it’ll be a lot easier
Good luck with future towers….170’
Last edited by 170'; 24th May 2009 at 13:23.