24 CFR § 51.301 - Definitions.

For the purposes of this regulation, the following definitions apply:

(a) Accident Potential Zone. An area at military airfields which is beyond the Clear Zone. The standards for the Accident Potential Zones are set out in Department of Defense Instruction 4165.57, “Air Installations Compatible Use Zones,” November 8, 1977, 32 CFR part 256. There are no Accident Potential Zones at civil airports.

(b) Airport Operator. The civilian or military agency, group or individual which exercises control over the operations of the civil airport or military airfield.

(c) Civil Airport. An existing commercial service airport as designated in the National Plan of Integrated Airport Systems prepared by the Federal Aviation Administration in accordance with section 504 of the Airport and Airway Improvement Act of 1982.

(d) Runway Clear Zones and Clear Zones. Areas immediately beyond the ends of a runway. The standards for Runway Clear Zones for civil airports are established by FAA regulation 14 CFR part 152. The standards for Clear Zones for military airfields are established by DOD Instruction 4165.57, 32 CFR part 256.