Special Use Airspace consists of airspace of defined dimensions identified by an area on the surface of the earth wherein activities must be confined because of their nature, or wherein limitations are imposed upon aircraft operations that are not a part of those activities, or both. The vertical limits of special use airspace are measured by designated altitude floors and ceilings expressed as flight levels or as feet above MSL. Unless otherwise specified, the word “to” (an altitude or flight level) means “to and including” (that altitude or flight level). The horizontal limits of special use airspace are measured by boundaries described by geographic coordinates or other appropriate references that clearly define their perimeter. The period of time during which a designation of special use airspace is in effect is stated in the designation. All bearings and radials in this part are true from point of origin. Unless otherwise specified, all mileages in this part are stated as statute miles.

Restricted Areas: No person may operate an aircraft within a restricted area between the designated altitudes and during the time of designation, unless they have the advance permission of:

(a) The using agency described in § 73.15; or

(b) The controlling agency described in § 73.17.

These using agencies may be the agency, organization, or military command whose activity within a restricted area necessitated the area being so designated. Upon the request of the FAA, the using agency shall execute a letter establishing procedures for joint use of a restricted area by the using agency and the controlling agency, under which the using agency would notify the controlling agency whenever the controlling agency may grant permission for transit through the restricted area in accordance with the terms of the letter. The using agency shall:

(1) Schedule activities within the restricted area;

(2) Authorize transit through, or flight within, the restricted area as feasible; and

(3) Contain within the restricted area all activities conducted therein in accordance with the purpose for which it was designated.

For the purposes of this part, the controlling agency is the FAA facility that may authorize transit through or flight within a restricted area in accordance with a joint-use letter issued under § 73.15.

Prohibited Areas: No person may operate an aircraft within a prohibited area unless authorization has been granted by the using agency. For the purpose of this subpart, the using agency is the agency, organization or military command that established the requirements for the prohibited area.

Military Operations Areas: A Military Operations Area (MOA) is airspace established outside of Class A airspace to separate/segregate certain nonhazardous military activities from IFR traffic and to identify for VFR traffic where these activities are conducted. Activities. MOA’s are established to contain certain military activities such as air combat maneuvers, air intercepts, acrobatics, etc.

Alert Areas:  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.

Warning Areas: A non regulatory warning area is airspace of defined dimensions designated over international waters that contains activity which may be hazardous to nonparticipating aircraft. The purpose of such warning areas is to warn nonparticipating pilots of the potential danger. Activities may be hazardous.

National Security Areas: A national security area (NSA) consists of airspace of defined vertical and lateral dimensions established at locations where there is a requirement for increased security of ground facilities. The purpose of such national security areas is to request pilot cooperation by voluntarily avoiding flight through the NSA. When circumstances dictate a need for a greater level of security, flight in an NSA may be temporarily prohibited by regulation under the provisions of 14 CFR Section 99.7, Special Security Instructions. Such prohibitions will be issued by FAA Headquarters and disseminated via the US NOTAM System.