Page 325 - The Complete Rigger’s Apprentice

Figure 8-7. Steve Dashew’s Sundeer.

that there is always a great deal of weather helm, 8-inch (203-mm)-diameter rudder shaft (!), and
all of it mizzen-induced. On most vessels this has a sacrificial “crushable” bottom; it’s extremely
would result in a hard-to-steer boat, but Sundeer unlikely that even a violent grounding would cause
has a large balanced spade rudder, so the helm significant damage.
always feels neutral. Why do this? Because a big, It is unusual to have rig and hull so creatively
properly shaped balanced rudder can provide lift, interlinked, but it’s possible to optimize the perfor-
just like a keel. If it can provide enough lift, you mance of any split rig relative to the hull it sits in.
can make the keel smaller and still go to weather On some boats this might involve flatter- or full-
well. So Sundeer’s rudder is helping the keel, just er-cut sails, adding a bowsprit, changing mast rake,
as the mizzen is helping the main. The net result etc. A qualified rigger or yacht designer can help
is that this 67-foot (20.4-m) LOD ketch draws you with particulars. Meanwhile, I hope this sec-
only 6 feet (1.8 m) loaded, yet will outpoint many tion has given you enough information to extrapo-
sloops, especially in a breeze, when speed gives late from, whether it’s for a configuration that will
the rudder more lift. Balanced spade rudders are allow you to disconnect a springstay, or to let you
generally frowned on by cruisers as fragile, vul- see force relationships more clearly, or just as an
nerable things, but Sundeer’s is built around an introduction to the next section.

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