17.44.030   Airport zones.
   In order to carry out the provisions of the ordinance codified in this chapter, there are hereby created and established certain zones which include all of the land lying beneath the approach surfaces, transitional surfaces, horizontal surfaces, and conical surfaces as they apply to the Chinook Airport, Harlem Airport, Turner Airport and Hogeland Airport. Such zones are shown on the respective airport airspace drawings and exhibits consisting of one sheet, prepared by the Blaine County airport board and dated June 2, 2003. The drawings and exhibits referenced herein are available for review and inspection at the office of the city clerk, Chinook, Montana. An area located in more than one of the following zones is considered to be only in the zone with more restrictive height limitation. The various zones are hereby established and defined as follows:
   "Utility Runway Visual Approach Zone" (Hogeland Airport) . The inner edge of this approach zone coincides with the width of the primary surface and is two hundred fifty feet wide. The approach zone expands outward uniformly to a width of one thousand, two hundred fifty feet at a horizontal distance of five thousand feet from the primary surface. Its centerline is the continuation of the centerline of the runway.
   "Utility Runway Nonprecision Instrument Approach Zone." The inner edge of this approach zone coincides with the width of the primary surface and is five hundred feet wide. The approach zone expands outward uniformly to a width of two thousand feet at a horizontal distance five thousand feet from the primary surface. Its centerline is the continuation of the centerline of the runway.
   "Runway Larger Than Utility Visual Approach Zone." The inner edge of this approach zone coincides with the width of the primary surface and is five hundred feet wide. The approach zone expands outward uniformly to a width of one thousand, five hundred feet at a horizontal distance of five thousand feet from the primary surface. Its centerline is the continuation of the centerline of the runway.
   "Runway Larger Than Utility With A Visibility Minimum Greater Than Three Fourths Mile Nonprecision Instrument Approach Zone."(Chinook Airport, Harlem Airport, Turner Airport Runway 7-25). The inner edge of this approach zone coincides with the width of the primary surface and is five hundred feet wide. The approach zone expands outward uniformly to a width of three thousand, five hundred feet at a horizontal distance of ten thousand feet from the primary surface. Its centerline is the continuation of the centerline of the runway.
   "Transitional Zones." The transitional zones are the areas beneath the transitional surfaces.
   "Horizontal Zone." The horizontal zone is established by swinging arcs from the center of each end of the primary surface of each runway and connecting the adjacent arcs by drawing lines tangent to those arcs. The radius of arc is:
      1.   Five thousand feet for all runways designated utility or visual;
      2.   Ten thousand feet for all others.
   The radius of the arc for each end of the runway shall be the same. The radius used shall be the longest determined for either end. The horizontal zone does not include the approach and transitional zones.
   "Conical Zone." The conical zone is established as the area that commences at the periphery of the horizontal zone and extends outward there from a horizontal distance of four thousand feet.
(Ord. 495 § 3, 2003).