Saturday 11 August 2012

You can't have too many rudders

In addition to twin rudders which have become a familiar design feature over the past ten years of so, this sports boat also has what appeared to be a steerable trim tab and horizontal control.

The twin rudders are quite short but presumably their location close to the waterline mean that the leeward rudder is effective when heeled.

Presumably the horizontal control reduces pitch and maintains for and aft trim plus contributes slightly to directional stability but I'm guessing it's real purpose is to generate downward force at speed to provide additional sail carrying capability (the keel is high aspect with a lead tear drop).


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  2. Three does seem a tad excessive... The horizontal section on the centre rudder is common on development class racing dinghies like the Cherub, Moth and National 12 (search for "t-foil rudder"). Where the aim is to actually give positive lift to the stern upwind, allowing the crew to move their weight backwards and aide planing. There's been a bit of experimentation in applying negative lift downwind in an effort to stop nosediving, but it never seems to end very well! It does of course help with controlling pitching in a chop as you say.

  3. which one yacht in good for ride in Dubai.
    yacht charter Dubai


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