Definition
Force applied by the pilot's left foot on the left rudder pedal to yaw the aircraft's nose to the left, coordinate a turn, or counteract a yawing tendency such as that produced by engine torque, P-factor, or slipstream effect.
Plain English
Pushing on the left rudder pedal with your left foot to make the nose move left or to keep the aircraft flying straight when something is pulling it to the right.
Context Anchor
Seen when using the turn-and-slip indicator during instrument flight, especially when the ball shows that rudder correction is needed.
Derivation
Rudder comes from an old word for a steering oar on a boat. That helps because an airplane’s rudder also steers by changing direction, but it does this in the air using the pilot’s foot pedals.
Why Pilots Care
Centers the inclinometer ball to prevent slipping or skidding during turns.
Intuition Check
Left rudder pressure does not mean turning the control wheel left. It means using your left foot on the rudder pedal to control the airplane’s yaw.
Example Sentence 1
As the bank steepened to the left, the pilot added a touch of left rudder pressure to keep the ball centered.
Example Sentence 2
Too little left rudder pressure in a left turn lets the ball slide right.