Once known as Hartley18
Join Date: Aug 2007
Location: Melbourne, Australia
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Re: Is external rudder a good idea?
The outboard hung rudder can have one serious fault: at higher speed and when a boat is well heeled over such a rudder can easily 'ventilate' or 'suck air down along the lower pressure side of the rudder' and the rudder will/can lose ALL control depending on the amount of ventilation.
Couple this with a helmsman who doesnt understand 'weather helm' requiring more rudder angle to overcorrect for adverse helm; include the vulnerability to 'ventilate' ........ and you can expect an unexpected 'pirouette' / unexpected rounding up as a worst case scenario in your future.
Stern hung rudders can easily 'ventilate'.
Totally submerged rudders have great difficulty in 'ventilating'.
Advantage - submerged rudders
That's complete rubbish, Rich.. C'mon, surely you know that.
modern boat that is is "well heeled" will have enough of the rudder exposed to 'ventilate' and potentially broach very soon thereafter if the helmsman isn't careful. You don't have to compete in many races or look in many books to see that.
If a single-rudder boat is so badly set up that the rudder doesn't "ventilate" to some extent at full heel, then dragging the tail around a racecourse won't win you any races either.
"Honestly, I don't know why seamen persist in getting wrecked in some of the outlandish places they do, when they can do it in a nice place like Fiji." -- John Caldwell, "Desperate Voyage"
Last edited by Classic30; 07-05-2013 at 01:51 AM.