Definition
A function of an area navigation (RNAV) or flight management system (FMS) that calculates and presents a vertical flight profile, allowing the pilot to plan and fly climbs, descents, and altitude crossings at specified points along the route.
Plain English
A feature in modern navigation computers that helps the pilot plan when to climb or descend so the aircraft arrives at the right altitude at the right place along the route.
Context Anchor
Seen in cross-country planning, descent planning, and avionics pages that help a pilot manage altitude along a route.
Derivation
Vertical refers to the up-and-down dimension of flight, as opposed to lateral (side-to-side) navigation. Navigation planning here means the system works out the path in advance, not just in the moment. Together: planning the aircraft's vertical path along the route before flying it.
Why Pilots Care
It keeps the flight within ATC altitude limits, avoids terrain, saves fuel, and produces a smooth descent profile.
Intuition Check
Do not read this as just “planning where to go.” In aviation, vertical navigation planning is specifically about the up-and-down part of the flight: altitude versus position along the route.
Example Sentence 1
The crew used the FMS vertical navigation planning feature to set up a continuous descent that met every altitude restriction on the arrival.
Example Sentence 2
Vertical navigation planning confirmed the aircraft could meet every crossing restriction on the published arrival.