Definition
In instrument flying, lead refers to the practice of beginning a maneuver — most commonly a turn, descent, or level-off — slightly before the target point or value, to compensate for the aircraft's momentum and the time required for the maneuver to take effect.
Plain English
Starting an action a little early so that you arrive at the right place or condition at exactly the right moment, instead of overshooting it.
Context Anchor
Used when planning turns during instrument navigation, especially when speed, turn size, or course changes could cause the airplane to overshoot the desired path.
Derivation
From Old English 'lædan,' meaning to guide or go in front. The aviation use keeps that sense — you go ahead of the event you're aiming for, so you arrive on target rather than past it.
Why Pilots Care
Correct lead prevents overshooting a course or fix, which maintains situational awareness and keeps the aircraft on published instrument procedures.
Analogy
It is like turning a car onto a road at speed: you do not wait until the front of the car reaches the exact corner and then turn sharply. You begin steering early enough to follow a smooth curve into the lane.
Grounding Statement
A faster airplane or a gentler turn needs more lead because it takes more space to complete the turn.
Intuition Check
Lead does not mean being in front of another aircraft here. It means starting an action before the exact point so the airplane arrives on the correct path.
Example Sentence 1
She began her lead about half a mile before the fix so the aircraft would roll out exactly on the inbound course.
Example Sentence 2
Applying the proper lead during the procedure turn kept the aircraft from overshooting the inbound radial.