A method established, or a procedure derived entirely from practice or experience not based on scientific knowledge; a roughly practical method.

A vertical shaft through which the turning force of the steering gear is transmitted to the rudder blade. The rudderstock is to be made of forged steel.

A mechanical arrangement which provides flexibility in the alignment of a driving and driven shaft, i.e. a flexible coupling.

Amount of carbon dioxide and other carbon compounds emitted due to the consumption of fossil fuels.

A lag on the stern frame or a bracket on deck at each side of the quadrant, to limit the swing of the rudder to approximately 37 deg port or starboard.

A fixed installation designed to displace the oxygen in the protected space and thus extinguish the fire, usually used to fight fires in engine rooms, boiler rooms, pump rooms and holds.

If the rudder blade has a sharp corner at the front lower edge, the flow cannot follow the sharp bend from the leading edge to the base plate causing cavitation in the front part of the rudder sole.

An adaptive control system that uses the existing steering gear and rudder.

Process of trapping carbon dioxide produced by burning fossil fuels or any other chemical or biological process and storing it in such a way that it is unable to affect the atmosphere.

Rudder propellers are azimuthing ducted or free-running propellers in a fixed or hinged vertical position. They are active control devices with a directed thrust.

Light decks fitted in ferries and ro-ro vessels. Except for pure car carriers, car decks are usually designed to be movable.

A one section ramp with flaps, integrated in a fixed or hoistable car deck panel, or just hinged or connected to the car deck edge.

A welded construction or a casting providing support for the rudder blade and minimises the bending moment in the rudderstock.

A fitting placed inboard (on the steering gear deck) which carries the whole weight of the rudder and the tiller. Rotary vane steering gears and some RAM-type steering gears have the rudder carrier integrated.

Vessels specially designed for efficient transport of cars (pure car carriers), or variety of cars, trucks, tractors and buses (pure car/truck carriers).

There are no regulation for the rating of the rudder area and very often crude empirical methods such as percentage of the underwater lateral area are used.

The main part of the rudder which provides the necessary surface for the impinging action and side pressure of the water

A device used to indicate the present position of the rudder blade, usually fitted in thewheelhouse, bridge wings and engine control room.

A hydraulic cylinder or a hydraulic motor which directly converts hydraulic pressure into mechanical action to move the rudder.

A device used for steering and manoeuvring a vessel. Rudders are hydrofoils which are pivoting on a vertical axis.