A ship's wheel or boat's wheel is a device used aboard a

water vessel Any vehicle used in or on water as well as underwater, including boats, ships, hovercraft and submarines, is a watercraft, also known as a water vessel or waterborne vessel. A watercraft usually has a propulsive capability (whether by sail, ...

to steer that vessel and control its course. Together with the rest of the

steering Steering is a system of components, linkages, and other parts that allows a driver to control the direction of the vehicle. Introduction The most conventional steering arrangement allows a driver to turn the front wheels of a vehicle using ...

mechanism, it forms part of the helm. It is connected to a mechanical, electric

servo Servo may refer to: Mechanisms * Servomechanism, or servo, a device used to provide control of a desired operation through the use of feedback ** AI servo, an autofocus mode ** Electrohydraulic servo valve, an electrically operated valve that c ...

, or

hydraulic system Hydraulics (from Greek: Υδραυλική) is a technology and applied science using engineering, chemistry, and other sciences involving the mechanical properties and use of liquids. At a very basic level, hydraulics is the liquid count ...

which alters the horizontal angle of the vessel's

rudder A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, aircraft, or other vehicle that moves through a fluid medium (generally air or water). On an aircraft the rudder is used primarily to counter adverse yaw a ...

relative to its hull. In some modern ships the wheel is replaced with a simple toggle that remotely controls an electro-mechanical or electro-hydraulic drive for the rudder, with a rudder position indicator presenting feedback to the

helmsman A helmsman or helm (sometimes driver) is a person who steers a ship, sailboat, submarine, other type of maritime vessel, or spacecraft. The rank and seniority of the helmsman may vary: on small vessels such as fishing vessels and yachts, the f ...

History

Until the invention of the ship's wheel, the helmsman relied on a

tiller A tiller or till is a lever used to steer a vehicle. The mechanism is primarily used in watercraft, where it is attached to an outboard motor, rudder post or stock to provide leverage in the form of torque for the helmsman to turn the rudder ...

—a horizontal bar fitted directly to the top of the

rudder post A rudder is a primary control surface used to steer a ship, boat, submarine, hovercraft, aircraft, or other vehicle that moves through a fluid medium (generally air or water). On an aircraft the rudder is used primarily to counter adverse ya ...

—or a whipstaff—a vertical stick acting on the arm of the ship's tiller. Near the start of the 18th century, a large number of vessels appeared using the ship's wheel design, but historians are unclear when the approach was first used.

Design

A traditional ship's wheel is composed of eight cylindrical wooden

spokes A spoke is one of some number of rods radiating from the center of a wheel (the hub where the axle connects), connecting the hub with the round traction surface. The term originally referred to portions of a log that had been riven (split l ...

(though sometimes as few as six or as many as ten) shaped like

balusters A baluster is an upright support, often a vertical moulded shaft, square, or lathe-turned form found in stairways, parapets, and other architectural features. In furniture construction it is known as a spindle. Common materials used in its cons ...

and all joined at a central wooden hub or ''nave'' (sometimes covered with a brass ''nave plate'') which housed the

axle An axle or axletree is a central shaft for a rotating wheel or gear. On wheeled vehicles, the axle may be fixed to the wheels, rotating with them, or fixed to the vehicle, with the wheels rotating around the axle. In the former case, beari ...

. The square hole at the centre of the hub through which the axle ran is called the ''drive square'' and was often lined with a brass plate (and therefore called a ''brass boss'', though this term was used more often to refer to a brass hub and nave plate) which was frequently etched with the name of the wheel's manufacturer. The outer rim is composed of sections each made up of stacks of three ''felloes'', the ''facing felloe'', the ''middle felloe'', and the ''after felloe''. Because each group of three felloes at one time made up a quarter of the distance around the rim, the entire outer wooden wheel was sometimes called the ''quadrant''. Each spoke ran through the middle felloe creating a series of handles beyond the wheel's rim. One of these handles/ spokes was frequently provided with extra grooves at its tip which could be felt by a helmsman steering in the dark and used by him to determine the exact position of the rudder—this was the ''king spoke'' and when it pointed straight upward the rudder was believed to be dead straight to the hull. The completed ship's wheel and associated axle and pedestal(s) might even be taller than the person using it. The wood used in construction of this type of wheel was most often either

teak Teak (''Tectona grandis'') is a tropical hardwood tree species in the family Lamiaceae. It is a large, deciduous tree that occurs in mixed hardwood forests. ''Tectona grandis'' has small, fragrant white flowers arranged in dense clusters (panicl ...

mahogany Mahogany is a straight- grained, reddish-brown timber of three tropical hardwood species of the genus '' Swietenia'', indigenous to the AmericasBridgewater, Samuel (2012). ''A Natural History of Belize: Inside the Maya Forest''. Austin: Un ...

, both of which are very durable tropical

hardwood Hardwood is wood from dicot trees. These are usually found in broad-leaved temperate and tropical forests. In temperate and boreal latitudes they are mostly deciduous, but in tropics and subtropics mostly evergreen. Hardwood (which comes fro ...

s capable of surviving the effects of salt water spray and regular use without significant decomposition. Modern design—particularly on smaller vessels—can deviate from the template.

Mechanism

The steering gear of earlier ships' wheels sometimes consisted of a double wheel where each wheel was connected to the other with a wooden ''spindle'' that ran through a ''barrel'' or ''drum''. The spindle was held up by two ''pedestals'' that rested on a wooden ''platform'', often no more than a grate. A ''tiller rope'' or ''tiller chain'' (sometimes called a ''steering rope'' or ''steering chain'') ran around the barrel in five or six loops and then down through two ''tiller rope/ chain slots'' at the top of the platform before connecting to two

sheave A sheave () or pulley wheel is a grooved wheel often used for holding a belt, wire rope, or rope and incorporated into a pulley. The sheave spins on an axle or bearing inside the frame of the pulley. This allows the wire or rope to move ...

s just below deck (one on either side of the ship's wheel) and thence out to a pair of pulleys before coming back together at the tiller and connecting to the ship's rudder. Movement of the wheels (which were connected and moved in unison) caused the tiller rope to wind in one of two directions and angled the tiller left or right. In a typical and intuitive arrangement, a forward-facing helmsman turning the wheel ''counter''clockwise would cause the tiller to angle to starboard and therefore the rudder to swing to port causing the vessel to also turn to port (see animation). On many vessels the helmsman stood facing the rear of the ship with the ship's wheel before him and the rest of the ship behind him— this still meant that the direction of travel of the wheel at its apex corresponded to the direction of turn of the ship. Having two wheels connected by an axle allowed two people to take the helm in severe weather when one person alone might not have had enough strength to control the ship's movements. When at the full extent of travel, the wheel and rudder are said to be "hard over", hence the order "hard

port A port is a maritime facility comprising one or more wharves or loading areas, where ships load and discharge cargo and passengers. Although usually situated on a sea coast or estuary, ports can also be found far inland, such as ...

starboard Port and starboard are nautical terms for watercraft and aircraft, referring respectively to the left and right sides of the vessel, when aboard and facing the bow (front). Vessels with bilateral symmetry have left and right halves which a ...

" given by

Captain Captain is a title, an appellative for the commanding officer of a military unit; the supreme leader of a navy ship, merchant ship, aeroplane, spacecraft, or other vessel; or the commander of a port, fire or police department, election precinct, e ...

Officer of the Watch Watchkeeping or watchstanding is the assignment of sailors to specific roles on a ship to operate it continuously. These assignments, also known at sea as ''watches'', are constantly active as they are considered essential to the safe operation o ...

Gallery

File:Britannia Yacht Club Commodore Boardroom.jpg,

Britannia Yacht Club The Britannia Yacht Club (BYC) is a private social club, yacht club and tennis club based in Britannia, Ottawa, Ontario, Canada. It was founded in 1887 by a group of cottagers. BYC is located on an extension of land at the eastern end of Lac ...

's Commodore Boardroom features a ship's wheel table File:Annunciator.jpg, USS ''LST-325'' ship's wheel and

engine order telegraph An engine order telegraph or E.O.T., also referred to as a Chadburn, is a communications device used on a ship (or submarine) for the pilot on the bridge to order engineers in the engine room to power the vessel at a certain desired speed. ...

File:US Navy 050823-N-9076B-001 Electrician's Mate 1st Class Aaron Walker speaks to chief petty officer selectees as he stands at the helm of USS Constitution in Boston.jpg, U.S. Navy personnel aboard , by the ship's wheel File:Kitee.vaakuna.svg, Ship's wheel pictured in the coat of arms of

Kitee Kitee ( sv, Kides) is a town and a municipality of Finland. It is located in the province of Eastern Finland and is part of the North Karelia region In geography, regions, otherwise referred to as zones, lands or territories, are areas that a ...

References

External links