Definition
An ARINC 424 path terminator leg that instructs the aircraft to fly a specified magnetic heading until reaching a defined altitude, at which point the leg ends and the next leg begins. The VA leg has no defined ground track and no fixed endpoint location — the leg terminates whenever the altitude is reached, so the actual geographic position at termination varies with wind, climb performance, and aircraft weight.
Plain English
It's a coded instruction in the flight plan that says 'fly this heading and keep climbing until you hit this altitude, then move on to the next instruction.' Where you actually end up on the map depends on how fast you climb and what the wind is doing.
Context Anchor
Seen in instrument procedure design and RNAV procedure coding, especially on departures and missed approach segments where the aircraft must climb on a heading before continuing.
Derivation
In the ARINC 424 path terminator system, each leg type is named by two letters. The first letter describes the path being flown (V = heading, vector); the second letter describes what ends the leg (A = altitude). So VA literally reads as 'heading-to-altitude.' Knowing the V/A pattern helps you decode related legs like CA (course to altitude) or VI (heading to intercept).
Why Pilots Care
Keeps the aircraft on the designed path for obstacle clearance until the required altitude is reached.
Grounding Statement
The important idea is that altitude, not position over the ground, is the trigger for ending this leg.
Intuition Check
Do not read this as simply “fly toward an altitude.” It means hold a specified heading, and stop that leg when the specified altitude is reached.
Example Sentence 1
The first leg of the departure was coded as a VA leg: fly heading 270° until passing 2,000 feet, then turn on course.
Example Sentence 2
The pilot maintained runway heading on the VA leg until the altimeter showed the published altitude.