Editing Ship (section)

=== Steering systems ===
[[File:Ferry-rudder-and-propeller.jpg|thumb|right|The rudder and propeller on a newly built [[Ferryboat|ferry]]]]

For ships with independent propulsion systems for each side, such as manual oars or some [[paddle steamer|paddles]],{{efn|Almost all paddle steamers had a single engine with their paddles permanently coupled, without any clutches, and so could not be used for steering. Only a few examples with separate engines were steerable. For example, the [[Royal Navy]] operated diesel–electric harbour tugs with paddles into the 1970s for their superior manoeuvrability.}} steering systems may not be necessary. In most designs, such as boats propelled by engines or sails, a steering system becomes necessary. The most common is a rudder, a submerged plane located at the rear of the hull. Rudders are rotated to generate a lateral force which turns the boat. Rudders can be rotated by a [[tiller]], manual wheels, or electro-hydraulic systems. [[Autopilot]] systems combine mechanical rudders with navigation systems. [[Ducted propeller]]s are sometimes used for steering.

Some propulsion systems are inherently steering systems. Examples include the [[outboard motor]], the [[bow thruster]], and the [[azimuth thruster]].