T&T: Steadying sails

[C. Marin Faure]

 >Hoisting a small amount of sail made a considerable difference in the
roll. A 50% reefed main (about 65 sq. ft.), sheeted amidships reduced
the total roll angle to about 20 degrees, 15 degrees to leeward and 5
degrees to windward.

Two things make this an apples and oranges comparison with a steady  
sail on the typical semi-planing hull trawler.  First, given the  
typical boom and mast dimensions and hardware configuration of a  
trawler like a GB36, you'll be lucky to carry as much as 30 or 40  
square feet of sail.  Second, the semi-planing hull with its wide,  
flat after-body and hard chines doesn't have the long, swoopy roll  
you'll get in a round-bottom boat like a Willard.  So there will be  
less movement of that small sail through the air to generate any sort  
of dampening force.  I've talked to a number of GB owners directly or  
on forums who have steady sails on their boats.  They say they do a  
relatively effective job of reducing hunting (yawing) on a mooring or  
at anchor in a wind.  But they all said the sail's effect is almost  
negligible as a stabilizer in a beam sea on a windy day.  Given the  
already high windage of a typical trawler like a GB, another 30  
square feet of surface just doesn't make that much difference,  
particularly since near the top of the mast where the leverage is  
greatest there are only a few square feet of sail to catch the wind.


____________________
C. Marin Faure
GB36-403 "La Perouse"
Bellingham, Washington