Definition
A historical class of controlled airspace surrounding certain busy airports, in which all aircraft were required to establish two-way radio communication with ATC and were provided with radar separation and traffic advisories. ARSAs were replaced by Class C airspace when the United States adopted the alphabetic airspace classification system in 1993.
Plain English
An older name for the controlled airspace around medium-sized busy airports where pilots had to talk to ATC and were tracked by radar. It is now called Class C airspace.
Context Anchor
Seen in older FAA material, acronym lists, airspace history, and discussions comparing older airspace names with current airspace classes.
Derivation
The name describes the function: an area around an airport where radar service is provided. Knowing this helps a pilot recognise that the modern Class C airspace is doing the same job under a new label.
Why Pilots Care
Pilots reading older training material, accident reports, or regulatory history may encounter ARSA and need to recognise that it refers to what is now Class C airspace, with the same communication and radar service requirements.
Intuition Check
Do not assume ARSA is a current airspace class you will normally see on modern charts. In most current training and flight planning, think of it as the older name for what became Class C-style radar-served airport airspace.
Example Sentence 1
The 1991 training manual still refers to the airspace around the airport as an ARSA, though today it would be charted as Class C.
Example Sentence 2
Aircraft inside the ARSA must follow ATC instructions for safe arrival and departure.