AIM 5-6-3

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.

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.

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.

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.

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.

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.

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.

Aeronautical facility , for the purposes of this section, means a communications facility where flight plans or position reports are normally filed during flight operations.