An articulated rudder is in two parts and basically bends in the middle – just like an articulated truck! Most rudders are in one piece, presenting a flat plate against the water. When you turn the wheel of the boat, the rudder turns and changes the angle at which water flows past you. This creates a lower pressure on one side of the rudder, and the boat turns away from it. A conventional rudder will also only work up to a certain angle – if you try to turn beyond that there is no effect.
The standard rudder works just fine at reasonable speeds – but at low speeds when trying to manoeuvre the boat, this can be difficult. Steering will only work when water is flowing at sufficient speed over the rudder. This creates a delay when you change directions as it takes a bit of time for the wash to build up enough, particularly if changing from forward to reverse.
An articulated rudder changes the angle at which the water flows past. It creates a sharper angle, which makes the rudder more responsive to changes. Advocates swear they can turn their boat in a circle on itself and that it replaces the need for stern and bow thrusters. Turned hard to one side, apparently you can move the boat sideways – without thrusters. We will reserve judgement until we have experienced this for ourselves.
Of course, Destiny comes equipped with bow and stern thrusters – as well as a remote joystick control, Dockmate. The articulated rudder is yet another redundancy system from that point of view – but its main purpose for us is to improve the boat handling with a following sea.
The biggest manufacturer of articulated rudders was Bayview Engineering. They have fitted a number of these units on Selene and other brands of trawlers. However, they have now ceased trading and the product is no longer easily available. Selene have therefore stepped into the breach and manufactured a custom-made articulated rudder, designed for us on 6043.
A lot of engineering thought has gone into the design – with input from Ed to this process as well. The additional force generated by the articulated rudder requires an upgrade to the steering pumps and the hydraulic rams. A structure is also engineered on top and on the foot of the rudder for reinforcement.