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Rudder

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{

"text": "A rudder is a primary control surface used to steer various vehicles. These vehicles move through a fluid medium, which can be water or air. This includes ships, boats, submarines, hovercraft, and airships. On an airplane, the rudder is used to counter adverse yaw and p-factor. However, it is not the primary control used to turn the aircraft.

Aileron yaw
Aileron yaw

\n\nThe rudder operates by redirecting the fluid past the hull or fuselage. This redirection imparts a turning or yawing motion to the craft. In its most basic form, a rudder is a flat plane. It is a sheet of material attached with hinges to the stern, tail, or afterend. To improve performance, rudders are often shaped to minimize hydrodynamic or aerodynamic drag.

Olympic stern and rudder
Olympic stern and rudder

\n\nDifferent types of steering mechanisms exist depending on the vessel. On simple watercraft, a helmsman might use a tiller. A tiller is essentially a stick or pole that acts as a lever arm. Larger vessels use more complex systems to move the rudder. These include cables, pushrods, or hydraulics. In a typical aircraft, the rudder is operated by pedals via mechanical linkages or hydraulics.

MM00756-4
MM00756-4

\n\nHistory shows that steering methods have evolved significantly over thousands of years. Ancient vessels used steering oars or paddles fastened outside the hull. These can be classified as side-rudders or stern-mounted rudders. In the Mediterranean, side-rudders were specifically called quarter-rudders. This name describes exactly where the rudder was mounted on the ship. Stern-mounted rudders are suspended in a central position at the back.

Rudder of a Roman Boat (RG Museum Koeln, Germany)
Rudder of a Roman Boat (RG Museum Koeln, Germany)

\n\nAncient Egyptian steering gear provides early examples of these tools. During the Old Kingdom, from 2686 to 2134 BC, passenger boats used many oars. Some boats had as many as five steering oars on each side. A tiller, which is a small pin through the steering oar stock, appeared during the fifth dynasty. The Greek historian Herodotus wrote about a rudder thrust through the keel.

Maler der Grabkammer des Menna 013
Maler der Grabkammer des Menna 013

\n\nRoman navigation also relied on highly refined steering systems. They used quarter steering oars that were mounted on the sides. By the first half of the 1st century AD, stern-mounted steering gear was common for river and harbor craft. Some Roman vessels, like the palace barges of Emperor Caligula, may have used rudders 14 meters long. These systems were effective, adaptable, and simple.

RudderBereFerrersBenchEnd
RudderBereFerrersBenchEnd

\n\nA major technological shift occurred in China during the 1st century

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🖼️ Images & Media (11)
File:Brosen propelersterntychy.jpg
Brosen propelersterntychy.jpg
File:Olympic stern and rudder.jpg
Olympic stern and rudder.jpg
File:Maler der Grabkammer des Menna 013.jpg
Maler der Grabkammer des Menna 013.jpg
File:Rudder of a Roman Boat (RG Museum Koeln, Germany).JPG
Rudder of a Roman Boat (RG Museum Koeln,...
File:Eastern Han pottery boat.JPG
Eastern Han pottery boat.JPG
File:Guo Zhongshu-Traveling on the River in Snow.jpg
Guo Zhongshu-Traveling on the River in Snow.jpg
File:Pottery boat from Eastern Han Dynasty showing rudder.jpg
Pottery boat from Eastern Han Dynasty...
File:Adler von Lübeck. Model ship 05.jpg
Adler von Lübeck. Model ship 05.jpg
File:RudderBereFerrersBenchEnd.jpg
RudderBereFerrersBenchEnd.jpg
File:Aileron yaw.gif
Aileron yaw.gif
File:MM00756-4.jpg
MM00756-4.jpg
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