Definition
A phrase used in airport classification and FAA planning documents to describe two of the measurable activity counts used to rank an airport's level of use: the number of instrument flight rules (IFR) operations conducted there, and the number of passengers handled. An 'operation' is one takeoff or one landing. These figures are used to determine an airport's category, funding eligibility, and service requirements.
Plain English
Two ways the FAA measures how busy an airport is: how many IFR takeoffs and landings happen there, and how many passengers pass through. These counts help decide what kind of airport it is and what services it qualifies for.
Context Anchor
Seen in FAA handbook and regulatory discussions about which operating rules apply to different types of flight operations.
Derivation
“Operations” comes from a word meaning work or activity. In aviation, it means the actual conduct of flights. “Passenger numbers” simply means the count of people being carried as passengers. Together, the phrase points to practical facts about the flight that can change the rules that apply.
Why Pilots Care
These numbers determine how an airport is classified, which affects available services, runway maintenance priority, control tower presence, and approach types. Knowing why a small field has limited services or why a busier one has more infrastructure often traces back to these counts.
Intuition Check
Do not read “or” as meaning both conditions must be present. In this phrase, IFR operations and passenger numbers are separate factors; either one may matter depending on the rule being discussed.
Example Sentence 1
The airport's category was based on its IFR operations or passenger numbers, both of which had grown over the past decade.
Example Sentence 2
Limits on IFR operations or passenger numbers can change the required equipment and crew for the flight.