If the desired effect is to have both the main and genoa projecting maximum area going dead down wind them both sails need to be set at right angles to the wind, which is about the same as right angle to the centerline of the boat.
Assuming a 155% LP and the foot at right angle to the boat the whisker pole would be > 184.5% of J. The ">" part is because the foot is larger than 155% of J. On my C&C 30-1 with a 13.5' J that comes out to slightly under 26'. I have found allowing a slight curve to the foot is OK, and having the angle a bit under 90 degrees is acceptable leaving a 24' whisker pole. I carry a 22' Forespar Line Control whisker pole, legal under PHRF Lake Ontario. In very light air I use all 22' of it. In heavier air on a reach I may use it to control sail shape, holds the clew at the proper spot and controls how much is being spilled off. The line control pole is adjustable so I can find a spot to raise the spinnaker car to that provides the combination of downward angle and distance needed. Michael Brown Windburn C&C 30-1 Sent: Friday, August 19, 2016 8:10 PM To: cnc-list@cnc-list.com Cc: Rick Brass Subject: Re: Stus-List Assymetrical spinnaker pole Depending on the size of your boat and the size of the sail you are poling out, your spin pole might be perfectly acceptable in lieu of a whisker pole. I?ve always understood the optimum length of a whisker pole is 80% of the LP of the sail being poled out. 80% of a 150 would be 1.2xJ. So if your J was 10?, as on a 27V, the spin pole would be about 24? less than optimal. On my 38 mk2 (J=16.3) with a 135, the difference between the spin pole and optimal whisker pole would only be about 15?. Rick Brass Washington, NC Subject: Re: Stus-List Assymetrical spinnaker pole I poled out my 155% genoa last night with the spin pole, because I don't have a whisker pole, and I found the spin pole to be almost too long. Cheers, Randy
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