Definition
An FAA database that records and reports passenger boardings (enplanements) and all-cargo landed weight at U.S. airports served by certificated air carriers. The data is used to classify airports by category (large hub, medium hub, small hub, nonhub, nonprimary) and to determine eligibility and apportionment of federal airport funding.
Plain English
An FAA system that keeps track of how many passengers and how much cargo move through each U.S. airport. Those numbers decide how an airport is officially classified and how much federal money it receives.
Context Anchor
Seen in FAA acronym lists and administrative material about air carrier operations, not as a normal cockpit item for student pilots.
Why Pilots Care
Pilots rarely use ACAIS directly, but its data drives whether an airport is labeled a large hub, small hub, or nonhub — which in turn affects funding for runways, towers, lighting, and other infrastructure pilots rely on.
Intuition Check
ACAIS may look like the name of an onboard aircraft system, but it is not. It is an FAA information system about air carrier activity.
Example Sentence 1
The airport's hub classification is updated each year using ACAIS enplanement data.
Example Sentence 2
Airport planners review ACAIS reports when evaluating future runway and terminal capacity needs.