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David,

I haven't made the change as the new rudder would be deeper than my wing keel. Not a good way to find the bottom. For a fin keel boat, I think it's a priority upgrade.

As Norm says, weather helm is rudder angle required to keep the boat from heading closer to the wind. A small amount of weather helm is desireable. The force you feel in the wheel from weather helm is caused by 2 factors - the rudder angle required to maintain course and the rudder balance that controls how much force is required to hold a given rudder angle at a given speed.

Balance is a product of hydrodynamic efficiency and balance ratio - that portion of the rudder blade that is forward of the center of the rudder shaft. Too much balance and you take away the feedback you get from the rudder, making the rudder dead or "twitchy". Too little balance, and you get a rudder that requires excessive force on the helm to control the boat - and that force increases quickly as more rudder is required.

A "perfect" rudder is hydrodynamically efficient - that is it generates lift a small angles of attack with minimum drag - and has a balance ratio that provides positive feedback to the helm while minimizing the forces the helmsman (or autopilot) has to counter.

The original rudder adequately controls the boat. In my opinion, it is an inefficient shape (requires too much angle of attack to generate lift) and has insufficient balance area so that the control forces build too quickly as more rudder movement is required. In 15-18 knots of wind, the boat is "cranky" and my kids have trouble controlling the helm in the gusts.

The new rudder is by design a more efficient blade and all reports are that it significantly improves performance and rudder feel. Unfortunately, those improvements are only available to captains with fin keels.

There's some interest in a new design rudder for wing keel boats, but only 3 or 4 owners have stepped up to say they are interested enough to consider buying one if it were available. It takes 15 or 20 (of several hundred wing keel boats out there) to justify the design and set up costs.

A long winded way of saying I think the new rudder is a priority upgrade for any fin keel boat and that I really wish a better blade was available for wing keel boats. I would order one today.

Regards,

Larry

Melelana
Catalina 42 #175
1990 3cbn, wk
Solomons, MD