Definition
A dynamic value, expressed in aircraft per hour, that represents the maximum number of arriving aircraft an airport, ATC facility, terminal area, or specified airspace can accept over a one-hour period. The AAR is set by air traffic management based on current conditions such as weather, runway configuration, and controller workload, and is used to plan and meter the flow of arrivals.
Plain English
The number of planes per hour that an airport can handle landing, given how things are running right now. If too many flights want to arrive, this rate tells controllers how to slow the flow down.
Context Anchor
Seen in air traffic flow planning, delay programs, and airport capacity discussions.
Derivation
“Rate” comes from an older word meaning a fixed amount or measured amount. In this term, it means a count measured over time: how many arrivals the airport can handle per hour.
Why Pilots Care
It helps pilots anticipate holding delays, adjust fuel loads, and plan arrival timing at busy or capacity-constrained airports.
Analogy
Think of a freeway off-ramp during rush hour. The off-ramp can only handle so many cars per hour before traffic backs up onto the highway. The AAR is that hourly limit for an airport.
Intuition Check
Do not read “rate” here as aircraft speed or climb/descent rate. In AAR, “rate” means how many arriving aircraft the airport can accept per hour.
Example Sentence 1
The AAR at the destination dropped from 48 to 30 because of a runway change, so dispatch issued a ground delay.
Example Sentence 2
Heavy rain lowered the AAR, so the flight was assigned a twenty-minute hold before being cleared for approach.