Inner Horizontal Surface . This surface is a plane , oval in shape at a height of 150 feet above the established airfield elevation . It is constructed by scribing an arc with a radius of 7,500 feet above the centerline at the end of the runway and interconnecting these arcs with tangents .
Conical Surface . This is an inclined surface extending outward and upward from the outer periphery of the inner horizontal surface for a horizontal distance of 7,000 feet to a height of 500 feet above the established airfield elevation . The slope of the conical surface is 20:1 ( 20 horizontal feet for one vertical foot ).
Outer Horizontal Surface . This surface is a plane located 500 feet above the established airfield elevation . It extends for a horizontal distance of 30,000 feet from the outer periphery of the conical surface .
Transitional Surfaces . These surfaces connect the primary surfaces , clear zones , and approach‐departure clearance surfaces to the outer horizontal surface , conical surface , other horizontal surface , or other transitional surfaces . The slope of the transitional surface is 7:1 outward and upward at right angles to the runway centerline . To determine the elevation for the beginning of the transitional surface slope at any point along the lateral boundary of the primary surface , including the CZ , draw a line from this point to the runway centerline . This line will be at right angles to the runway axis . The elevation at the runway centerline is the elevation for the beginning of the 7:1 slope .
Imaginary Surfaces for Runway 007 / 187 ( Maxwell AFB Landing Zone ) As referred to in the 2009 Maxwell AFB AICUZ Update , the following provides a description of each of the imaginary surfaces associated with the Landing Zone ( LZ ), Runway 007 / 187 . It should be noted this runway is 3,015 feet long by 60 feet wide . This runway is primarily used for C‐130 Maxwell AFB crews to perform tactical departure and arrival training . Periodically , transient C‐130 aircrews also use the LZ for training sorties .
Primary Surface . This surface defines the area the LZ . The elevation of any point on this surfac the nearest point on the runway centerline or e The primary surface for Runway 007 / 187 is 150
Clear Zone Surface . This surface is an area on t beginning at the runway threshold and is symm runway centerline . It is graded and designed to for which only properly located NAVAIDs are all
Maintained Area . This surface is a land area ex angles from the runway centerline and the exte This area is located outside the graded area and and must be free of obstructions . For Runway 0 is 60 feet wide . The grade may slope up or dow may not exceed a + 10 percent or ‐20 percent sl
Exclusion Area . This surface is an area that is r and is restricted to development of facilities aro allowable features in this area include taxiways aircraft and support equipment . This area exte and the CZ on each end . The Exclusion Area for 1,000 feet as this area is occupied .
Approach‐Departure Clearance Surface . This s that of the Approach‐Departure Clearance Surfa 15 / 33 . However , the slope and length associate reduced . The slope is 35:1 ( 35 horizontal feet f remains constant throughout the length of the from Runway 15 / 33 . The length of this area is 1 two miles from the runway centroid .
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