Definition
On a turn-and-slip indicator, a skid indication is shown when the ball rolls to the outside of the turn, indicating that the rate of turn is too high for the angle of bank — the aircraft is being pushed sideways toward the outside of the turn due to insufficient bank for the rate of yaw being applied.
Plain English
The ball has slid to the outside of the turn. This means you are turning too fast for how steeply the wings are banked. The fix is to add more bank or reduce the rate of turn until the ball returns to the center.
Context Anchor
Seen on the turn-and-slip indicator, also called the needle and ball, during instrument turns.
Derivation
Skid comes from an old word meaning to slide sideways without control, like a car skidding outward on a curve. The aircraft is doing the same thing — sliding toward the outside of the turn instead of carving cleanly through it.
Why Pilots Care
An uncorrected skid wastes energy, increases stall risk in the turn, and can lead to spatial disorientation in instrument conditions.
Analogy
It is like a car taking a corner too sharply and sliding outward instead of following the curve smoothly.
Intuition Check
A skid indication does not mean the airplane’s tires are skidding on the runway. In this instrument context, it means the ball is showing that the airplane is sliding outward in a turn.
Example Sentence 1
The instructor pointed out the skid indication and told the student to add a little more bank or ease off the inside rudder to recenter the ball.
Example Sentence 2
During the instrument approach turn the skid indication disappeared once the pilot matched bank and rudder.