Weather Helm
Now that Natalie and I have semi-retired from racing I thought I would share something that came to light only towards the end of our racing days. What is the greatest source of weather helm on a Flying Scot? 1 Rudder Angle, 2 Too Much Heal, 3 Sail Trim, 4 Other? The answer 4 Other. It's the point of attachment for the main-sheet strap on the rudder head. The main-sheet, at this attachment point, is pulling the front of the rudder head away to leeward inducing weather helm. If you move the strap 1&1/4" aft, then you will take away most of the weather helm. 2" back will make the helm go neutral, and 3" back will give lee helm – assuming our rudder rake position. Many FS sailors sail with the rudder straight down. This may give a false sense of easing pressure on the blade, but will actually facilitate snapping the blade at the turning point underneath the rudder head. Try moving the strap an 1&1/4" back, and sail with some rake in the rudder blade. We sailed the rudder blade 2 to 3 inches back measured from the front of the rudder head down parallel to the tip and then 2&3/4" back. If you move the main-sheet strap 1&1/4" back - the factory rudder rake will feel great. Many young sailors, who jump into the class, often complain about the excessive weather helm compared to other classes. I used to see many sailors break rudder blades at Panama City FL from sailing in heavy air, off the wind, with straight down blades. Sweeping the blade back will move the pressure from the tip, and move it up towards the middle of the blade spreading the force over a greater surface area. Another advantage of having some sweep on the flat rudder blade means moving the rudder less - reducing the braking effect of the straight-down blade. Good Sailing.
Scott Mauney
Thu, 12/09/2010 - 15:43
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Thank you Hank for getting the forums back on-line! Weather H
Thank you Hank for getting the forums back on-line!
Weather Helm #2
How did this come to my attention? At the 2005 FS NAC I put the strap on the rear bolt by accident. When we went out before the first qualifier, Bill Draheim, the skipper told me he had severe lee helm. Finally I realized what I had done. We had no time to change it so we kicked the rudder blade back to where the aft tip was almost out of the water - to balance the excessive lee helm. We sailed the remainder of regatta with strap in the normal forward bolt location. When I got my new boat I decided to experiment using the 3 new holes. Final analysis: I use the forward hole up to 8 knots of breeze and the next hole back at 1&1/4" for anything over 8 knots. Here is a link showing the second hole. I just add another stainless bolt and nut and move the strap back. Draheim told me the helm feels like a Melges 24 with the strap in this position.
[ed. Here's a Picture:]