Definition
A vertical flight path computed by the Flight Management System (FMS) that defines the desired altitudes and vertical speeds along a route, typically used to descend or climb the aircraft along a planned path between waypoints. The profile is built from altitude constraints stored in the flight plan (such as crossing restrictions at named fixes) and the aircraft's performance data, and the FMS uses it to generate vertical guidance for the autopilot or pilot to follow.
Plain English
A planned up-and-down path the FMS works out for the flight, showing what altitude the aircraft should be at over each point along the route. The autopilot or pilot then flies the aircraft to match that path.
Context Anchor
Seen when using an FMS to plan, monitor, or adjust climbs and descents, especially when the route includes altitude limits to meet.
Derivation
VNAV stands for vertical navigation. 'Profile' comes from the Italian profilo, meaning a side view or outline. A VNAV profile is literally the side-view outline of the flight — the shape of the climb and descent drawn against altitude.
Why Pilots Care
Allows the aircraft to fly continuous, fuel-efficient descents while automatically meeting all altitude restrictions without constant pilot intervention.
Grounding Statement
Picture the route from the side: the VNAV profile is the line showing where the aircraft should be vertically along that route.
Intuition Check
Profile does not mean a pilot biography or a general setting here. It means the planned vertical shape of the flight path.
Example Sentence 1
After loading the arrival, the crew reviewed the VNAV profile to confirm the aircraft would meet the crossing restriction at the initial approach fix.
Example Sentence 2
Before starting the arrival, the pilot verified that the VNAV profile would keep the aircraft above all minimum altitudes on the published procedure.