NSA
Airspace of defined dimensions identified by an area on the surface of the earth wherein activities must be confined because of their nature and/or wherein limitations may be imposed upon aircraft operations that are not a part of those activities:
- Alert Area- Airspace which may contain a high volume of pilot training activities or an unusual type of aerial activity, neither of which is hazardous to aircraft.
- Controlled Firing Area- Airspace wherein activities are conducted under conditions so controlled as to eliminate hazards to nonparticipating aircraft and to ensure the safety of persons and property on the ground.
- Military Operations Area (MOA)- Permanent and temporary MOAs are airspace established outside of Class A airspace area to separate or segregate certain nonhazardous military activities from IFR traffic and to identify for VFR traffic where these activities are conducted.
- National Security Area (NSA)- Airspace of defined vertical and lateral dimensions established at locations where there is a requirement for increased security of ground facilities.
- Prohibited Area- Airspace designated under 14 CFR part 73 within which no person may operate an aircraft without the permission of the using agency.
- Restricted Area- Permanent and temporary restricted areas are airspace designated under 14 CFR part 73, within which the flight of aircraft, while not wholly prohibited, is subject to restriction.
- Warning Area- A warning area is airspace of defined dimensions extending from 3 nautical miles outward from the coast of the United States, that contains activity that may be hazardous to nonparticipating aircraft.
Listed in the Pilot/Controller Glossary as a cross-reference to SPECIAL USE AIRSPACE, whose text is shown above.
Source FAA Pilot/Controller Glossary · checked 2026-08-25