Some Tips from the Top
Use Sail Trim to Help Turn Your Boat
By David Dellenbaugh
Easton, Connecticut
Fleet 726, Cedar Point Yacht Club
1991 World Champion
(From Racing the Lightning)
Everyone knows you turn a boat with the rudder. This
directs the stern of the boat in one direction and turns the boat by
pivoting it around the centerboard or keel. However, steering with the
rudder has a couple of limitations: first, you can’t turn if you are
not moving very fast because the rudder only works when water is flowing
over its surface.
Second, steering with the rudder slows you down. The
further you push the tiller to one side, the more the rudder’s surface
area will be exposed to the flowing water, and the more the rudder will
act as a brake.
Because the rudder has disadvantages, you must use
other turning methods if you want to go faster. Here’s where the sail
trimmer plays an important role. You may have noticed on a windy day,
for example, that the skipper has a hard time bearing off around the
windward mark unless he or she dumps the mainsheet. On big boats, the
sail trimmers often have more control over the direction of the boat
than the helmsperson!
Just like the rudder, your sails can be used to help
turn the boat around its underwater pivot point. Sailboards are a great
example of how this works. Since boards don’t have rudders, they rely
on the position of the sail for turning. When a board sailor wants to
bear off, she pushes the whole sail forward over the bow.
This puts more wind pressure forward of the center
board, so the bow pivots to leeward.
The same principle applies to a sailboat. If you want
to turn away from the wind, pull the jib tight and let the main out.
.This moves the effective sail area forward, which pushes the bow away
from the wind and pivots the boat around the centerboard. If you want to
head up toward the wind let the jib out and trim the main in tight. Now
the working sail area is behind the centerboard, so the boat will head
up.
As a sail trimmer, you should use these techniques
any time the boat changes course. It’s very important to ease the
main, for example, whenever you are rounding a windward mark, bearing
off behind a starboard tacker or trying to keep from rounding up on a
reach. Likewise, you should ease the jib a little any time you are
luffing into a tack or rounding a leeward mark.
If you consistently use sail trimming techniques to
help turn your boat, your gains around the race course will be
significant.
Try this: on your next practice day, sail out into
open water and remove your rudder. Then practice turning the boat with
your sails only. This requires good coordination between the helmsperson
on the mainsheet and the forward crew on the jib sheet. If it’s windy,
you may need to raise the centerboard a little to move the center of
lateral resistance aft and reduce weather helm.