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The easier way to connect the steering oar to its stock is
first to hook the shock cord to the stock, then swing the
steering oar in position over the stock until the two pins are
snug into the notches.
Safety line
Should we mention it? It is essential to have a safety line
on the steering oar, to avoid seeing it disappear in the wake,
the first time it breaks off.
Flipping the steering oar up when underway
The easiest method of flipping the paddle up when under way is to tilt the windvane
crescent, which will cause the servo-pendulum to swing to one side, then pull it up out
of the water to “ park ” it along the tower.
Ideal size of the servo-pendulum
Power generated by the servo-pendulum is proportional to its wetted area and to
the square of the speed of the boat. From this, we conclude that servo-pendulum area
is critical only at low speed. At higher speeds, the pendulum generates considerably
more power than needed to steer the boat.
Experience has shown that the wetted area of servo-pendulum needed to steer at
2-3 kts to be somewhere between 8 and 12 % of the yacht’s rudder area. Closer to 8
for a high aspect-ratio, partially balanced rudder steering a well balanced boat, and
closer to 12 (or more) for a low aspect ratio rudder, on a boat that is not so well
balanced, or has a wheel steering system with a lot of internal friction. We normally
take the yacht’s rudder dimensions and the height of the horizontal axis above the
waterline in determining the length of the servo-pendulum for a given boat, but if you
find that your pendulum does not generate adequate power to steer your boat at slow
speeds, please contact us and we will provide you with a longer one.
A racer concerned with reducing drag to a minimum could order two steering oars :
a longer one for light air or slow speed, and a shorter one for higher speeds.
Internal resistance of a cable steering system can be reduced appreciably by
loosening the tension on the steering cables. This can be done before a passage
when the vane will be steering most of the time. Loosening the cables may induce a
little “ backlash ” in the wheel, but since the vane will be doing most of the steering, this
is of little consequence.
Balance under sail
With any kind of self-steerer or autopilot the secret to top performance is sail
balance.
