Section 27.20  Definitions

As used in this Part, unless the context otherwise requires:

            "Airport" – The Casey Municipal Airport located near Casey, situated in Section 19, Township 10 North, Range 14 East of the Second Principal Meridian, Clark County, Illinois; also known as Casey Municipal Airport.

            "Airport Elevation" – The established elevation of the highest point on the usable landing strip; the established airport elevation shall be 654 feet above mean sea level (AMSL).

            "Airport Hazard" – Any structure, tree, or use of land which obstructs the airspace required for, or is otherwise hazardous to the flight of aircraft in landing or taking-off at the airport. (Section 3 of the Act)

            "Airport Reference Point" – The point established as the approximate geographic center of the airport landing area and so designated as at Latitude 39°  18' 11.0" N and Longtitude 88°  00' 18.0" W.

            "Alteration" – Any construction which would result in a change in height or lateral dimensions of an existing structure.

            "Approach, Transitional, Horizontal and Conical Surfaces" – These surfaces are defined in Section 27.30.

            "Circling Approach Area" – That obstacle clearance area which shall be considered for aircraft maneuvering to land on a runway which is not aligned with the final approach course of the approach procedure.

            "Construction" – The erection or alteration of any structure either of a permanent or temporary character.

            "Department" – The Department of Transportation, Division of Aeronautics of the State of Illinois.

            "Departure Area" – That area which begins at the departure end of the runway and has a beginning width of 1000' (500' from centerline).  The area splays 15° on each side of the extended runway centerline for a distance of 2 Nautical Miles (NM).  Additionally, it includes a second surface that extends radially from a point on the runway centerline located 2,000' from the start end of the runway and extends the distance necessary to provide a 40:1 obstacle identification surface to reach the minimum altitudes authorized for en route operations.

            "Final Approach Segment" – That area of an approach where the aircraft makes final alignment and descent for landing.

            "Flight Safety Coordinator" – An employee of the Department whose duties include, but are not limited to inspection of airports, review of complaints concerning uses of property in the vicinity of airports and inspection of structures, uses and trees in the vicinity of airports to determine if such structures, uses or trees impair the use of the airport by aircraft.

            "Height" – The overall height of the top of a structure including any appurtenances installed thereon, for the purpose of determining the height limits in all zones set forth in this Part and shown on the zoning map, the datum of which shall be mean sea level elevation unless otherwise specified.

            "Initial Approach Segment" – That area of an instrument approach between a point where aircraft departs the enroute phase of flight and is maneuvering to enter an intermediate segment.  Such approach segments may be made along an arc, radial, course, heading, radar vector or a combination of thereof.

            "Intermediate Approach Segment" – That area of an approach between the initial and final approach segments where the aircraft adjusts configuration, speed and positioning along positive course guidance such as radial or course.

            "Landing Area" – The area of the airport used for the landing, taking-off or taxiing of aircraft including the unprepared surfaces adjacent to the existing runways.

            "Minimum Instrument Flight Altitude" – An altitude established for instrument flight between radio fixes that provides obstacle clearance over the terrain and man-made objects and adequate for navigational performance and communications requirements.

            "Non-Conforming Use" – Any structure, tree, or use of land which is lawfully in existence at the time this Part or an amendment thereto becomes effective and does not than meet the requirements of this Part.

            "Non-Precision Instrument Runway" – A runway having an existing instrument approach 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 by the Federal Aviation Administration [FAA], or planned, and for which no precision approach facilities are planned, or indicated on an FAA planning document or military service, military airport planning document.

            "Obstacle Clearance" – The vertical distance between the lowest authorized flight altitudes and a prescribed surface within a specified area.

            "Permit" – A permit issued by the Department of Transportation, Division of Aeronautics, pursuant to Section 27.60 of this Part.

            "Person" – An individual, firm, partnership, corporation, company, association, joint stock association, or body politic, and includes a trustee, receiver, assignee, administrator, executor, guardian, or other representative, and including this state and the Division of Aeronautics.  (Section 7 of the Act)

            "Political Subdivision" – any municipality, city, incorporated town, village, county, township, district, or authority, or any combination of two or more thereof,  situated in whole or in part within any of the surfaces established by Section 27.30.  (Section 6 of the Act)

            "Precision Instrument Runway" – A precision instrument runway is one which uses an instrument landing system (ILS) or precision approach radar (PAR).  A planned precision instrument runway is one for which a precision approach system is indicated on a Department approved Airport Layout Plan, which is on file at the Department of Transportation, Division of Aeronautics, Bureau of Engineering, One Langhorne Bond Drive/Capital Airport, Springfield, Illinois 62706.

            "Runway" – An area of the airport designated for the landing or taking off of aircraft and consisting of turf or concrete, asphalt, oil and chip or other composite material that forms an all weather surface other than turf.

            "Slope Ratio" – A numerical expression of a stated relationship of height to horizontal distance, e.g. 100 to 1 means one hundred feet of horizontal distance for each one foot vertically.

            "State" – The State of Illinois.  (Section 8 of the Act)

            "Structure" – Any form of construction or apparatus of a permanent or temporary character, constructed or installed by man, including any implements or material used in the erection, alteration or repair of such structure, including but without limitation, buildings, towers, smokestacks, and overhead transmission lines.

            "Terminal Obstacle Clearance Area" – That area near an airport that contains the initial, intermediate and final approach segments, circling and departure areas which are a part of an instrument approach procedure.

            "Tree" – Any object of natural growth.

            "Utility Runway" – A runway that is constructed for and intended to be used for propeller driven aircraft of 12,500 pounds maximum gross weight or less.

            "Variance" – A grant of relief by the Department from the requirements of this Part, in accordance with Section 27.80.

            "Visibility Minimums" – The lowest forward horizontal distance from the cockpit of an aircraft in flight at which prominent unlighted objects may be seen and identified by day and prominent lighted objects may be seen and identified by night.

            "Visual Runway" – A visual runway is a runway intended solely for the operation of aircraft using visual approach procedures with no straight-in instrument approach procedure and no instrument designation indicated on a Department approved Airport Layout Plan, which is on file at the Department of Transportation, Division of Aeronautics, Bureau of Engineering, One Langhorne Bond Drive/Capital Airport, Springfield, Illinois 62706.