I'd say It's BS because boats are simply not that rigid and it's hard to
measure to an accuracy of 4 thou on big objects. The flexability of most
boats is such that the side stays limit the spread of the hull as the
backstay is tightened (this is naval architecture 101). Current rig
tensions are much higher than they used to be. Even Ella has a backstay
tension of 2,500 lbs when beating.

Cheers MC

DSK wrote:

The_navigator© wrote:

4 thou. measured on the back of a boat? Complete BS.


"The Captain...cap n all" wrote:
I would have thought so.


AFAIK there was no reason to BS about it, the boat was a one-off
and paid for. If I am interpreting the article about the boat
correctly, the distortion was measured at the mid length along a
straight from stem to center transom.

If one is installing high powered hydraulics to control the rig,
it makes sense to make the hull & deck structure as rigid as
possible, within reasonable weight limits. I haven't seen any
figures for the distortion measured on the newest IACC boats but
the early 1990s boats had very high rig loads (10K kg and up)
and very little (if any) distortion.

Fresh Breezes- Doug King