AIM DECODED

5-6-3. Definitions

AIM Text

  1. Air Defense Identification Zone (ADIZ) means an area of airspace over land or water, in which the ready identification, location, and control of all aircraft (except Department of Defense and law enforcement aircraft) is required in the interest of national security.
  2. Defense Area means any airspace of the contiguous U.S. that is not an ADIZ in which the control of aircraft is required for reasons of national security.
  3. U.S. territorial airspace, for the purposes of this section,means the airspace over the U.S., its territories, and possessions, and the airspace over the territorial sea of the U.S., which extends 12 nautical miles from the baselines of the U.S., determined in accordance with international law.
  4. To U.S. territorial airspace means any flight that enters U.S. territorial airspace after departure from a location outside of the U.S., its territories or possessions, for landing at a destination in the U.S., its territories or possessions.
  5. From U.S. territorial airspace means any flight that exits U.S. territorial airspace after departure from a location in the U.S., its territories or possessions, and lands at a destination outside the U.S., its territories or possessions.
  6. Within U.S. territorial airspace means any flight departing from a location inside of the U.S., its territories or possessions, which operates en route to a location inside the U.S., its territories or possessions.
  7. Transit or transiting U.S. territorial airspace means any flight departing from a location outside of the U.S., its territories or possessions, which operates in U.S. territorial airspace en route to a location outside the U.S., its territories or possessions without landing at a destination in the U.S., its territories or possessions.
  8. Aeronautical facility, for the purposes of this section, means a communications facility where flight plans or position reports are normally filed during flight operations.

Source: FAA Aeronautical Information Manual · current edition · paragraph 5-6-3.

The short answer

This advisory AIM section defines key national-security airspace terms, including Air Defense Identification Zone (ADIZ), Defense Area, and U.S. territorial airspace. It explains that an ADIZ requires ready identification, location, and control of aircraft in the interest of national security, and that U.S. territorial airspace extends 12 nautical miles from the U.S. baselines, supporting 14 CFR part 99.

Research Notes

Common Questions

What is an Air Defense Identification Zone (ADIZ)?

The AIM defines an ADIZ as an area of airspace over land or water in which the ready identification, location, and control of all aircraft, except Department of Defense and law enforcement aircraft, is required in the interest of national security. A Defense Area is contiguous U.S. airspace that is not an ADIZ but where aircraft control is required for national security.

How far does U.S. territorial airspace extend?

For purposes of this section, the AIM defines U.S. territorial airspace as the airspace over the U.S., its territories, and possessions, and over the territorial sea, which extends 12 nautical miles from the baselines of the U.S., determined in accordance with international law.

What is the difference between transiting and operating within U.S. territorial airspace?

Per the AIM definitions, "transiting" means a flight departing outside the U.S. that operates in U.S. territorial airspace en route to a location outside the U.S. without landing inside it. "Within" U.S. territorial airspace means a flight that both departs from and operates en route to a location inside the U.S., its territories, or possessions.