"Howie" wrote in message
...
On Mon, 10 May 2004 10:48:22 GMT, "Martin Underwood"
wrote:

|This is probably an incredibly naive question, and I apologise if it's a
|FAQ, but it's one of those things that I was pondering on in an idle
moment.
|
|Why is it that on all boats, the rudder is at the back rather than the
front
|of the boat? Is it:
|
|- because a rudder at the front simply wouldn't work properly to steer
the
|boat?
|
|- because a rudder at the back gives greater manoeuvrability, in the same
|way that dumper trucks on building sites have rear-wheel steering whereas
|cars and lorries have front-wheel steering?

It's to do with displacement. A displacement hull is designed to
'fend off' water whilst travelling forwards.
A rudder at the front would stop the displacement hull working
effeciently unless you are travelling in a straight line. So - it
slows the boat down.

Also, Because the boat is designed to go at maximum speed when
going forwards, the water stream passing under and around the
boat is much more stable and reliable as a medium than the water
you have not yet hit! Effectively, the water speed and direction
helps the rudder to do it's job. A rudder hinders the effeciency
of this water stream, this is how it operates. You wouldn't want
the rudder to hinder the water-stream before the hull gets a
chance to move through it!

Sounds intelligent enough and believable, but then explain canard wings on
aircraft...? That's basically a rudder in front.

I also think this question could be given a lot of insight by some sweep
boaters; they have rudders/oars at both ends, and those guys are well
acquianted with steering with one or the other against the current
differential. Any sweep-oarsmen out there?

--riverman

--riverman