Rudder

steering · water and air · vehicles

Catches the flow. A rudder works by redirecting water or air past a vehicle's hull or fuselage, which makes the whole craft turn or spin. It's like putting your hand out a car window and angling it to push against the wind.

Hinged flat panel. In its simplest form, a rudder is just a flat sheet of material attached with hinges to the back (stern or tail) of a vehicle. Rudders are often shaped smoothly to reduce drag and work as efficiently as possible.

Different controls fit different sizes. On small boats, a helmsman might move a rudder with a simple stick called a tiller. On huge ships, cables and hydraulics (special fluid-powered systems) connect the rudder to a big steering wheel so many people can help steer.

Airplanes use pedals. Airplane rudders work differently than boat rudders because planes need to prevent a twisting motion called yaw. Pilots control the rudder with foot pedals connected by mechanical linkages or hydraulics, not to turn the plane but to keep it steady.

Shaped for speed. Modern rudders are carefully designed to minimize drag, which means they slice through water or air with the least resistance possible. This keeps vehicles moving smoothly and efficiently.