For the purpose of this article, the terms used herein are defined as follows:
AIRPORT ELEVATIONThe highest point of an airport's usable landing area measured in feet from sea level, which is 465 feet.
APPROACH SURFACEA surface longitudinally centered on the extended runway center line, 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 §
84-111 of this article. In plan, the perimeter of the approach surface coincides with the perimeter of the approach zone.
CONICAL SURFACEDA surface extending outward and upward from the periphery of the horizontal surface at a slope of 20:1 for a horizontal distance of 4,000 feet.
HAZARD TO AIR NAVIGATIONAn obstruction determined to have a substantial adverse effect on the safe and efficient utilization of the navigable airspace.
HEIGHTFor the purpose of determining the height limits in all zones set forth in this article and shown on the Zoning Map, the datum shall be mean sea level elevation unless otherwise specified.
HORIZONTAL SURFACEA horizontal plane 150 feet above the established airport elevation, the perimeter of which in plan coincides with the perimeter of the horizontal zone.
NONPRECISION INSTRUMENT RUNWAYA runway having an existing instrument-approach procedure utilizing air navigation facilities with only horizontal guidance or having area-type navigation equipment for which a straight-in nonprecision-instrument-approach procedure has been approved or planned.
OBSTRUCTIONAny structure, growth or other object, including a mobile object, which exceeds a limiting height set forth in §
84-111 of this article.
PRIMARY SURFACEA surface longitudinally centered on a runway. When the runway has a specially prepared hard surface, the primary surface extends 200 feet beyond each end of that runway; 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 500 feet. The elevation of any point on the primary surface is the same as the elevation of the nearest point on the runway center line.
RUNWAYA defined area in an airport prepared for landing and takeoff of aircraft along its length.
STRUCTUREAs defined in §
84-8, but also to include any object, including a mobile or immobile object, constructed or installed by man, including but without limitation buildings, towers, cranes, smokestacks, earth formation and overhead transmission lines.
TRANSITIONAL SURFACESThese surfaces extend outward at ninety-degree angles to the runway center line and the runway center line extended at a slope of seven feet horizontally for each foot vertically from the sides of the primary and approach surfaces to where they intersect the horizontal and conical surfaces.
TREEAny object of natural growth.