Definition
A path and terminator leg type used in RNAV procedure coding in which the aircraft flies a specified magnetic heading until it reaches a defined altitude, at which point the leg terminates and the next leg begins. The VA leg has no fixed lateral endpoint; the terminator is the altitude itself, not a waypoint or distance.
Plain English
Fly the heading the procedure tells you to fly, and keep flying it until you climb (or descend) through the altitude the procedure specifies. As soon as you hit that altitude, that part of the procedure is over and you move on to the next instruction.
Context Anchor
Seen in RNAV and instrument procedure coding, especially when describing how a published procedure is built from path-and-terminator legs.
Derivation
In ARINC 424 procedure coding, every leg has a two-letter type code. The first letter describes the path, the second describes how the leg terminates. V stands for heading (as opposed to a course or track), and A stands for altitude. So VA literally reads as 'heading-to-altitude.'
Why Pilots Care
Tells the FMS or autopilot exactly when to stop flying the assigned heading and transition to the next segment, preventing overshoot or early turns.
Intuition Check
Do not read this as “fly toward an altitude” as if altitude were a place on the map. The aircraft flies a heading, and the altitude is the trigger that ends the leg.
Example Sentence 1
After takeoff, the departure procedure begins with a VA leg: fly runway heading until passing 1,500 feet, then turn on course.
Example Sentence 2
The FMS flew the VA leg until the aircraft leveled at the published altitude, then sequenced to the next waypoint.