17.17.030 DEFINITIONS

As used in this title, unless the context otherwise requires: AIRPORT: The Logan-Cache Airport or any area of land designated and used for the landing and taking off of aircraft. AIRPORT ELEVATION: The highest point of an airport's usable landing area measured in feet from mean sea level. This elevation is four thousand four hundred fifty seven feet (4,457') MSL as of the effective date hereof. AIRPORT HAZARD: Any structure or use of land which actually or potentially obstructs the airspace required for the safe flight of aircraft in landing or taking off at an airport. APPROACH SURFACE: A surface longitudinally centered on the extended runway centerline, extending outward and upward from the end of the primary surface and at the same slope as the approach zone height limitation slope set forth in section 17.17.090 of this chapter. In plan, the perimeter of the approach surface coincides with the perimeter of the approach zone. APPROACH, TRANSITIONAL, HORIZONTAL AND CONICAL ZONES: These zones are set forth in section17.17.080 of this chapter. CONICAL SURFACE: A surface extending outward and upward from the periphery of the horizontal surface at a slope of twenty to one (20:1) for a horizontal distance of four thousand feet (4,000'). FAR PART 77: Federal aviation administration regulations pertaining to height and obstruction criteria within prescribed distances from an airport as these regulations currently exist and as may be amended from time to time. Part 77 regulations may also affect lands located outside the boundaries of the defined airport influence area. HAZARD TO AIR NAVIGATION: An obstruction determined to have a substantial adverse effect on the safe and efficient utilization of the navigable airspace. HEIGHT: For the purpose of determining the height limits in all zones set forth in subsection17.17.090D of this chapter and shown on the zoning map, the datum shall be the mean sea level (MSL) elevation unless otherwise specified. HELIPORT PRIMARY SURFACE: The primary surface coincides in size and shape with the designated takeoff and landing area of a heliport. This surface is a horizontal plane at the elevation of the established heliport elevation. HORIZONTAL SURFACE: A horizontal plane one hundred fifty feet (150') above the established airport elevation, the perimeter of which in plan coincides with the perimeter of the horizontal zone. Ldn: Yearly day-night average sound level. LARGER THAN UTILITY RUNWAY: A runway that is constructed for and intended to be used by propeller driven aircraft of greater than twelve thousand five hundred (12,500) pounds maximum gross weight and jet powered aircraft. MSL: Mean sea level. NONCONFORMING USE: Any preexisting structure, object or natural growth, or use which is inconsistent with the provisions of this title or an amendment thereto. NONPRECISION INSTRUMENT RUNWAY: 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 nonprecision instrument approach procedure has been approved or planned. It also means a runway for which a nonprecision approach system is planned and is so indicated on an approved airport layout plan or any other planning document. OBSTRUCTION: Any structure, growth or other object, including a mobile object, which exceeds a limiting height set forth in subsection 17.17.090D of this chapter. PERSON: An individual, firm, partnership, corporation, company, association, joint stock association or governmental entity; includes a trustee, a receiver, an assignee, or a similar representative of any of them. PRECISION INSTRUMENT RUNWAY: A runway having an existing instrument approach procedure utilizing an instrument landing system (ILS), a precision approach radar (PAR), a global positioning system (GPS), a transponder landing system (TLS), or other systems providing both horizontal and vertical guidance. It also means a runway for which a precision approach system is planned and is so indicated on an approved airport layout plan or any other planning document. PRIMARY SURFACE: A surface longitudinally centered on a runway. When the runway has a specially prepared hard surface, the primary surface extends two hundred feet (200') beyond each end of that runway; for military runways or when the runway has no specially prepared hard surface, or planned hard surface, the primary surface ends at each end of that runway. The width of the primary surface is set forth in subsection 17.17.080E of this chapter. The elevation of any point on the primary surface is the same as the elevation of the nearest point on the runway centerline. RUNWAY: A defined area on an airport prepared for landing and takeoff of aircraft along its length. STRUCTURE: An object, including a mobile object, constructed or installed by man, including, but not limited to, buildings, towers, cranes, smokestacks, earth formations and overhead transmission lines. TRANSITIONAL SURFACES: These surfaces extend outward at ninety degree (90°) angles to the runway centerline and the runway centerline extended at a slope of seven feet (7') horizontally for each foot vertically from the sides of the primary and approach surfaces to where they intersect the horizontal and conical surfaces. Transitional surfaces for those portions of the precision approach surfaces, which project through and beyond the limits of the conical surface, extend a distance of five thousand feet (5,000') measured horizontally from the edge of the approach surface and at ninety degree (90°) angles to the extended runway centerline. TREE: Any object of natural growth. UTILITY RUNWAY: A runway that is constructed for and intended to be used by propeller driven aircraft of twelve thousand five hundred (12,500) pounds maximum gross weight and less. VISUAL RUNWAY: A runway intended solely for the operation of aircraft using visual approach procedures.