Any locality, either of land or water, including airports and intermediate landing fields, which is used or intended to be used for the landing and takeoff of aircraft, whether or not facilities are provided for shelter, servicing or repair of aircraft or for receiving or discharging passengers or cargo.

Any landing area used regularly by aircraft for receiving or discharging passengers or cargo; or for the landing and takeoff of aircraft being used for personal or training purposes.

The extension, alteration, addition to or realignment of the runway(s) of an existing airport, or the modification in any way of the landing or takeoff directions at such an airport.

A trapezoidal area formed by the projection of the approach surface onto the ground directly below the approach surface. Approach zone dimensions are the same as those of the associated approach surface and vary according to runway category, as shown in Exhibit C for airports and Exhibit D for heliports (Appendix A-6, infra) (see “approach surface”, subdivision [d] of this section).

That surface which is longitudinally centered on a runway or landing area centerline extending the full length of either side of, and 200 feet beyond the ends of, a runway. It is the same elevation as the nearest point of the runway centerline. The primary surface width will vary according to the runway category (see dimension A on Exhibit A). The primary surface of a helipad is the overall size of the landing area (see dimensions R & S on Exhibit B) (Appendix A-6, infra).

An area on each side of the primary surface of the runway or landing area and approach surface. The lateral transition surface slopes upward and outward on a seven-to-one plane for airports and a two-to-one plane for heliports (see Exhibits C and D [Appendix A-6, infra] for applicable lateral transition surface dimensions for airports and heliports, respectively). The same clearances apply for lateral transition surfaces as apply for approach surfaces (see Exhibits A and B [Appendix A-6, infra]).

An area on the ground formed by the projection of the lateral transition surface onto the ground directly below the lateral transition surface. Lateral transition zone dimensions are the same as those of the associated lateral transition surface and vary according to runway category, as shown in Exhibit C for airports and Exhibit D for heliports (Appendix A-6, infra) (see “lateral transition surface”, subdivision [g] of this section).

A runway intended solely for the operation of aircraft using visual approach procedures, with no straight-in instrument approach procedure and no instrument designations. There are two types of visual runways:

A runway having an existing instrument approach procedure utilizing air navigation facilities with only horizontal guidance, or area-type navigation equipment, for which a straight-in, non-precision instrument approach procedure has been approved, or planned, and for which no precision approach facilities are planned, or indicated on an approved FAA planning document.

A runway having an existing instrument approach procedure utilizing an Instrument Landing System (ILS). It also means a runway for which a precision approach system is planned and is also indicated on an FAA-approved airport layout plan or any other FAA planning document.

An Instrument Landing System (ILS) is a system which provides aircraft the lateral, longitudinal and vertical guidance necessary for a landing.

Either a landing or takeoff by an aircraft.

Any contrivance, now or hereafter invented, for avigation of or flight in the air, except a parachute or other contrivance designed for use as, and carried primarily for, safety equipment.

An airport used exclusively by helicopters (see “airport”, subdivision [b] of this section).

That part of a body of water on which seaplane operations take place.

The centerline of approach surfaces (see “approach surface”, subdivision [d] of this section).