This is on a 46' Classic in S. Florida. New owner said according to PO it helps a lot. Don't know if the Prop Speed will work on the rudder and trim tabs though.
This is on a 46' Classic in S. Florida. New owner said according to PO it helps a lot. Don't know if the Prop Speed will work on the rudder and trim tabs though.
Helps what? Martini’s and boobs come to mind here. One is not enough three is too many.
Seems to me it would have been easier to either enlarge both rudders, or at least add a fishtail to both.
Guy has a SD boat powered probably with big Cats, and he's wondering why it handles like garbage at 7 knot trawler speeds and in heavy following/quartering seas.
Seems to me it would have been easier to either enlarge both rudders, or at least add a fishtail to both.
Guy has a SD boat powered probably with big Cats, and he's wondering why it handles like garbage at 7 knot trawler speeds and in heavy following/quartering seas.
Agreed, larger / better rudders in the 2 existing positions would have been a much better way to do this. Like many SD boats, that GB looks to be under-ruddered from the factory to either idiot-proof handling at high speeds or to get a little more top end speed. In my opinion, unless the boat is a go-fast, the rudders should be sized for cruising just below hull speed and accept the slightly loss of top end (and that applying full rudder at high speeds may be a bad idea).
It does have a bow thruster, stabilizers as well. IMO the thrusters, meh, but I can appreciate the desire for better steerage.
I too feel the GB's are under ruddered and would like better low speed and heavy seas control. I cross a bar coming in the Jupiter inlet (narrow and swift) and in a following sea its thrilling.
Would adding a fishtail unbalance the rudders too much? How much area would be needed to appreciably improve the handling? Anyone done this?
My question too. Three rudders . . . that's a new one on me, other than on a boat with three engines, such as an older Pluckebaum or the like, built back when diesel was less than a dollar a gallon.
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"Less judgment than wit is more sail than ballast. Yet it must be confessed that wit give an edge to sense, and recommends it extremely." ~ William Penn
Not so uncommon on Tugboats, called "Flanking Rudders." For the obvious reasons of slow speed control, these "extra" rudders are mounted as twin behind the props, outboard, or even in front of the props.
Given what this probably cost, articulated rudders may have cost close to the same but provided better performance. I have no experience with them myself, but everyone that has raves about the performance and I've never heard of someone second guessing the choice.
Dave Gerr goes into rudder sizing in detail in his book, "The Nature of Boats".
I agree that it adds drag and won't help much at low speeds. -- I'd take it off and, if necessary, add area to the two existing rudders. That assumes that their shafts are robust enough to stand the increased loading that would generate.
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