rudder under power
of course under power your prop is flowing water over the rudder at much higher velocity than if you are just sailing. As the rudder rotates it is subjected to much higher loads from this higher velocity stream. Remember F=ma and since the mass of water hitting the rudder instantaneously is the same (a function of rudder area) what you are dealing with is a high acceleration as the water hits the rudder, loses velocity and is redirected in a different direction. Since acceleration is the instantaneous change in velocity over time the fact that the velocity is faster is resulting in a higher force. This does not explain why the wheel is seizing up , only why the forces being applied to the cables, and chain and pedestal are higher. Obviously something is jamming up and you need to go thru the whole system to determine what. The edson wheel is basically a sprocket with a chain and a cable attached to each chain end and lead around sheaves and attached to the rudder quadrant. Take off the compass and look down the pedastal for anything out of the ordinary, crawl underneath and look at the condition of cables and sheaves and quadrant attachments, finally look at the rudder and bearing system, perhaps some grease is in order, higher loads on the rudder mean more friction in the tube and without grease this could be wearing. best of luck and tell us what you find dave
