Definition
The first altitude assigned by ATC after takeoff or upon clearance, which the pilot is expected to climb to and maintain until further altitude instructions are issued.
Plain English
The altitude controllers tell you to level off at first after departure. You hold that altitude until they clear you higher.
Context Anchor
Seen when filing or reviewing an instrument flight plan with Flight Service, and when receiving departure instructions from a controller.
Derivation
Initial comes from a Latin word meaning “beginning.” Altitude comes from a Latin word meaning “height.” Together, the term points to the height used at the beginning of the flight or segment.
Why Pilots Care
It gives immediate vertical separation from terrain and traffic during the departure phase.
Intuition Check
Initial altitude does not mean the highest altitude for the whole flight. It means the first altitude used at the start, before later climbs, descents, or changes.
Example Sentence 1
Cleared to Centennial, climb and maintain 8,000 -- our initial altitude is 8,000.
Example Sentence 2
After takeoff the pilot climbed directly to the initial altitude before contacting departure.