A yoke is a primary control device used for piloting some fixed-wing aircraft. Known as the control column or control wheel, it is a mechanical system connected directly to control surfaces. By manipulating the yoke, the pilot manually adjusts the aircraft's elevator and ailerons, thereby controlling pitch, roll, and overall attitude. The device may be panel-mounted or floor-mounted, and it remains standard in many Boeing models, while a side stick offers an alternative control method.
Expert behind this article
Jim Goodrich
Jim Goodrich is a pilot, aviation expert and founder of Tsunami Air.
What is a yoke in an airplane?
A yoke, alternatively known as a control wheel, is used for piloting some fixed-wing aircraft. It controls the attitude of the plane, and when pulled back, the nose of the aircraft rises. An aircraft yoke is a U-type or circular control wheel found in the cockpit of many conventional fixed-wing airplanes; it is the fundamental fixture the pilot uses to command ailerons and elevators. Smaller aircraft's yokes are attached directly to the instrument panel with a sturdy tube, while the shape is U, M, W, or even a ram's horn style like that used on Embraer aircraft.
What does the yoke control in an airplane?
The yoke controls pitch and roll. Fore and aft movement of the control column controls the elevator; when you pull the yoke back the elevator goes up and the nose rises and when you push it forward the elevator goes down and the nose lowers. Rotating the control wheel controls the ailerons; when you turn the yoke right the right aileron goes up and the left aileron goes down, banking the airplane right, and the opposite motion banks it left. Thus, by twisting the yoke side to side the pilot commands roll, and by moving it fore and aft the pilot commands pitch, giving the primary control of attitude.
How does a plane yoke work?
The pilot yoke operates with a collection of mechanical parts like cables, rods, chains and pulleys. A small sprocket connects chain and cable to a complementary chain and sprocket on the copilot side, so the yoke and copilot yoke turn together because of this chain and cable linking sprockets. Fore and aft movement of the control column controls the pitch axis. When the control column is pulled back it pulls the nose of the aircraft up by raising the stabilator's trailing edge whereas when the control column is pushed forward it pitches the nose down by lowering the stabilator's trailing edge. Rotating the control wheel controls the roll axis: moving the control wheel to the right causes the right aileron to deflect upward and the left aileron to deflect downward, making the aircraft roll right, while turning the wheel left produces the opposite effect. Ailerons are mounted on the trailing edge of each wing near the wingtips and are connected to the control wheel by cables, pulleys, bellcranks and push-pull tubes. Cables are guided by a series of pulleys to move one aileron up and deflect the opposite aileron down.
Human muscle power alone is not enough for larger aircraft, so hydraulic systems are used, and in modern fly-by-wire systems the physical connection between pilot controls and flight control surfaces is replaced by an electrical interface.
What are the types of plane yokes?
Control yokes are available in several styles. The most common shapes are ‘U’ and ‘W’. Some aircraft use an M-style yoke, which is alternatively called a ‘ram's horn’ yoke. Embraer and Concorde aircraft use the M-style yoke. Conventional yokes are panel-mounted or floor-mounted’ when floor-mounted, the post protruding vertically from the floor is referred to as a control column. Typical light aircraft have dual yokes that are directly connected so that moving one moves the other. Side yokes, or side sticks, are used on modern aircraft like Cirrus SR20, SR22, Airbus jets, Bombardier CSeries and Sukhoi Superjet. They are more lightweight than traditional yokes and allow a larger instrument display.
Why is an airplane yoke called a yoke?
Airplane yokes are called as such because the term ‘yoke’ is simply the next step after the earlier joystick control. Yoke is derived from the joystick control that became standard on aircraft when Glenn Curtiss personally ran the company. In the early machines, Curtiss needed a way to control ailerons and rudder, so a single upright lever - literally a stick - was the obvious answer. When cockpits grew cramped and two-handed leverage was needed, that same stick evolved into a U-style or W-style bar: the pilot's two hands now grasped the ‘horns’ of what looked like an ox-yoke, giving the device its name.
