Which airspace classification is related to national security areas?

The classification of airspace related to national security areas is Restricted Airspace. This type of airspace is designated for the purpose of limiting access to specific areas to protect national security interests. It generally indicates that certain activities are conducted within that airspace that may be hazardous to non-participating aircraft, which can include military operations or tests involving munitions. In Restricted Airspace, the flight of aircraft is restricted or prohibited unless permission is obtained from the controlling agency.

National security areas, while they share some purposes with Restricted Airspace, are not officially classified as restricted airspace; they indicate areas where flight is discouraged due to conditions that could pose threats to national security. Thus, Restricted Airspace is the more appropriate classification when discussing specifically designated airspace for national security purposes.

The other classifications—like Prohibited Airspace, which prohibits all flight; Airport Advisory Areas, mainly for flight planning in relation to nearby airports; and Controlled Firing Areas, where activities may occur but do not prohibit flight—do not encompass the protective measures associated directly with national security areas in the same manner as Restricted Airspace does.