(a) The following imaginary surfaces are established to implement the provisions of this division.
(b) The dimensions, elevations above mean sea level, slopes and radii applicable to the imaginary surfaces shall be as shown on the zoning map.
(1) Primary surface. A surface longitudinally centered on a runway, and extending beyond the ends of the runway. The elevation of any point on the primary surface is the same as the elevation of the nearest point on the runway centerline.
(2) Horizontal surface. A horizontal plane surface 150 feet above the established airport elevation, the perimeter of which is constructed by swinging arcs of specified radii from the center of each end of the primary surface of each runway and connecting the adjacent arcs by lines tangent to those arcs.
(3) Conical surface. A surface extending outward and upward from the entire perimeter of the horizontal surface, at a specified slope and for a specified distance.
(4) Approach surface. A surface longitudinally centered on the extended runway centerline and extending outward and upward from each end of the primary surface for a specified distance at a specified slope, and expands its horizontal dimension uniformly to a specified width.
(5) Transitional surfaces. A surface extending outward and upward at right angles to the runway centerline and the runway centerline extended at a specified slope from the sides of the primary surface and from the sides of the approach surfaces. Transitional surfaces for those portions of the conical surfaces extend a specified distance measured horizontally from the edge of the approach surface and at right angles to the runway centerline.
(Ord. 6687, § 4, passed 6-10-1972)