A/FD-
(See AIRPORT/FACILITY DIRECTORY.)

AFFIRMATIVE- Yes.
AFIS-
(See AUTOMATIC FLIGHT INFORMATION
SERVICE - ALASKA FSSs ONLY.)

AFP-
(See AIRSPACE FLOW PROGRAM.)
AIM-
(See AERONAUTICAL INFORMATION
MANUAL.)

AIP [ICAO]-
(See ICAO term AERONAUTICAL
INFORMATION PUBLICATION.)

AIR CARRIER DISTRICT OFFICE- An FAA field office serving an assigned geographical area, staffed with Flight Standards personnel serving the aviation industry and the general public on matters related to the certification and operation of scheduled air carriers and other large aircraft operations.
AIR DEFENSE EMERGENCY- A military emer-gency condition declared by a designated authority. This condition exists when an attack upon the continental U.S., Alaska, Canada, or U.S. installa-tions in Greenland by hostile aircraft or missiles is considered probable, is imminent, or is taking place.
(Refer to AIM.)
AIR DEFENSE IDENTIFICATION ZONE (ADIZ)-The area of airspace over land or water, extending upward from the surface, within which the ready identification, the location, and the control of aircraft are required in the interest of national security.
a..
Domestic Air Defense Identification Zone. An ADIZ within the United States along an international boundary of the United States.

b..
Coastal Air Defense Identification Zone. An ADIZ over the coastal waters of the United States.

c.
Distant Early Warning Identification Zone (DEWIZ). An ADIZ over the coastal waters of the State of Alaska.

d..Land-Based Air Defense Identification Zone. An ADIZ over U.S. metropolitan areas, which is activated and deactivated as needed, with dimen-sions, activation dates and other relevant information disseminated via NOTAM.
Note: ADIZ locations and operating and flight plan requirements for civil aircraft operations are speci-fied in 14 CFR Part 99.
(Refer to AIM.)
AIR NAVIGATION FACILITY- Any facility used in, available for use in, or designed for use in, aid of air navigation, including landing areas, lights, any apparatus or equipment for disseminating weather information, for signaling, for radio‐directional finding, or for radio or other electrical communica-tion, and any other structure or mechanism having a similar purpose for guiding or controlling flight in the air or the landing and takeoff of aircraft.
(See NAVIGATIONAL AID.)
AIR ROUTE SURVEILLANCE RADAR- Air route traffic control center (ARTCC) radar used primarily to detect and display an aircraft's position while en route between terminal areas. The ARSR enables controllers to provide radar air traffic control service when aircraft are within the ARSR coverage. In some instances, ARSR may enable an ARTCC to provide terminal radar services similar to but usually more limited than those provided by a radar approach control.