Definition
In ATC usage, the determination that an aircraft meets the criteria to receive a particular service, clearance, route, or procedure. Eligibility may depend on aircraft equipment, pilot certification, performance capability, filed flight plan type, or operational conditions at the time of the request.
Plain English
Whether an aircraft qualifies to use a specific service or procedure, based on what it has on board, who is flying it, what it can do, and what it filed for.
Context Anchor
Seen in FAA and air traffic control material when something is available only to pilots, aircraft, or flights that meet stated requirements.
Derivation
From Latin eligere, meaning 'to choose' or 'to select out.' The word still carries that sense: being eligible means you have been selected as qualifying — you meet the conditions to be chosen for something.
Why Pilots Care
Determines whether a flight can legally and safely use a particular route, approach, or airspace; failure to confirm eligibility can result in denied clearance or violation.
Intuition Check
Eligibility does not mean something is automatically provided. It means the requirements are met, so the person, aircraft, or flight may be allowed to use or receive it.
Example Sentence 1
Because the aircraft was not RVSM-equipped, it had no eligibility for a cruising altitude in the FL290–FL410 band.
Example Sentence 2
Eligibility for the RNAV approach required both the proper navigation database and current pilot training.