Hi guys,
what is the primary purpose of a surfski rudder?
On a sailboat, you have a rudder far aft, and a keel somewhere in the middle. The keel is meant to keep direction, the rudder is meant to change direction, put simply.
On a surfski, the rudder is meant to change your direction, you might think. My take is that a surfski rudder is rather meant to keep your direction, and specifically to prevent you from broaching when on a wave.
Therefore it is not so relevant whether your ski can turn on a dime on flat water. It is more important that it keeps you on track when all sorts of lateral powers are pushing at your stern and bow. Of course it is nice when the boat turns well when on a wavecrest. But most of the time you will rather want to stay your course instead of changing it, right?
Why do I want to discuss this? I design boats from time to time, have them built or build them myself, and then outfit them with a rudder. But I am always asking myself what the ideal position of the rudder (distance to the stern) might be. On 640 elite skis, this is at about 80 to 90 cm, but it differs a lot among different models. Do skis with rudders farther aft tend more to broaching while turning better on the flat?
what is the primary purpose of a surfski rudder?
On a sailboat, you have a rudder far aft, and a keel somewhere in the middle. The keel is meant to keep direction, the rudder is meant to change direction, put simply.
On a surfski, the rudder is meant to change your direction, you might think. My take is that a surfski rudder is rather meant to keep your direction, and specifically to prevent you from broaching when on a wave.
Therefore it is not so relevant whether your ski can turn on a dime on flat water. It is more important that it keeps you on track when all sorts of lateral powers are pushing at your stern and bow. Of course it is nice when the boat turns well when on a wavecrest. But most of the time you will rather want to stay your course instead of changing it, right?
Why do I want to discuss this? I design boats from time to time, have them built or build them myself, and then outfit them with a rudder. But I am always asking myself what the ideal position of the rudder (distance to the stern) might be. On 640 elite skis, this is at about 80 to 90 cm, but it differs a lot among different models. Do skis with rudders farther aft tend more to broaching while turning better on the flat?
