(a)The following airport imaginary surfaces
are established with relation to any public-use airport and to each
runway:
(1)Horizontal surface: a horizontal plane one hundred fifty (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 of each
airport and connecting the adjacent arcs by lines tangent to those
arcs. The radii of each arc is five thousand (5,000) feet for all
runways designated as utility or visual, and ten thousand (10,000)
feet for all other runways.
(2)Conical surface: a surface extending outward and upward
from the periphery of the horizontal surface at a slope of twenty
(20)to one (1) for a horizontal distance of four thousand (4,00
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(a) The following airport imaginary surfaces
are established with relation to any public-use airport and to each
runway:
(1) Horizontal surface: a horizontal plane one hundred fifty (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 of each
airport and connecting the adjacent arcs by lines tangent to those
arcs. The radii of each arc is five thousand (5,000) feet for all
runways designated as utility or visual, and ten thousand (10,000)
feet for all other runways.
(2) Conical surface: a surface extending outward and upward
from the periphery of the horizontal surface at a slope of twenty
(20) to one (1) for a horizontal distance of four thousand (4,000)
feet.
(3) Primary surface: a surface longitudinally centered on a
runway. When the runway has a specially prepared hard surface,
the primary surface extends two hundred (200) feet beyond each
end of the runway, but when the runway has no specially prepared
hard surface, the primary surface ends at each end of that runway.
The width of a primary surface is the following:
(A) Two hundred fifty (250) feet for utility runways having only
visual approaches.
(B) Five hundred (500) feet for utility runways having
nonprecision instrument approaches.
(C) For other than utility runways, the width is the following:
(i) Five hundred (500) feet for visual runways having only
visual approaches.
(ii) Five hundred (500) feet for nonprecision instrument
runways having visibility minimums greater than three-fourths
(3/4) of a statute mile.
(iii) One thousand (1,000) feet for a nonprecision instrument
runway, having a nonprecision instrument approach with
visibility minimums as low as three-fourths (3/4) of a statute
mile, and for precision instrument runways.
(4) Approach surface: a surface longitudinally centered on the
extended runway centerline and extending outward and upward
from each end of the primary surface. An approach surface is
applied to each end of each runway based upon the type of
approach available or planned for that runway end. The following
also applies to the approach surface:
(A) The inner edge of the approach surface is the same width as
the primary surface and it expands uniformly to a width of the
following:
(i) One thousand two hundred fifty (1,250) feet for that end of
a utility runway with only visual approaches.
(ii) One thousand five hundred (1,500) feet for that end of a
runway other than a utility runway with only visual approaches.
(iii) Two thousand (2,000) feet for that end of a utility runway
with a nonprecision instrument approach.
(iv) Three thousand five hundred (3,500) feet for that end of a
nonprecision instrument runway other than utility, having
visibility minimums greater than three-fourths (3/4) of a statute
mile.
(v) Four thousand (4,000) feet for that end of a nonprecision
instrument runway, other than utility, having a nonprecision
instrument approach with visibility minimums as low as
three-fourths (3/4) of a statute mile.
(vi) Sixteen thousand (16,000) feet for precision instrument
runways.
(B) The approach surface extends for a horizontal distance of
the following:
(i) Five thousand (5,000) feet at a slope of twenty (20) to one
(1) for all utility and visual runways.
(ii) Ten thousand (10,000) feet at a slope of thirty-four (34) to
one (1) for all nonprecision instrument runways other than
utility.
(iii) Ten thousand (10,000) feet at a slope of fifty (50) to one (1)
with an additional forty thousand (40,000) feet at a slope of
forty (40) to one (1) for all precision instrument runways.
(5) Transitional surfaces: these surfaces extend outward and
upward at right angles to the runway centerline and the runway
centerline extended at a slope of seven (7) to one (1) from the
sides of the primary surface and from the sides of the approach
surfaces. Transitional surfaces for those portions of the precision
approach surface which project through and beyond the limits of
the conical surface, extend a distance of five thousand (5,000) feet
measured horizontally from the edge of the approach surface and
at right angles to the runway centerline.
(b) As used in subsection (a) in establishing airport imaginary
surfaces:
"Nonprecision instrument runway" means a runway having an
existing instrument approach procedure utilizing air navigation
facilities with only horizontal guidance, or area type navigation
equipment, for which a straight-in nonprecision instrument approach
procedure has been approved, or planned, and for which no precision
approach facilities are planned, or indicated on a Federal Aviation
Administration planning document.
"Precision instrument runway" means a runway having an existing
instrument approach procedure utilizing an instrument landing system
(ILS), microwave landing system (MLS), or a precision approach radar
(PAR). It also means a runway for which a precision approach system
is planned and is so indicated by a Federal Aviation Administration
approved airport layout plan or other planning document.
"Utility runway" means a runway that is constructed for and
intended to be used by propeller driven aircraft of twelve thousand five
hundred (12,500) pounds maximum gross weight or less.
"Visual runway" means 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 Federal Aviation Administration approved airport layout
plan or any other planning document.
(c) The following heliport imaginary surfaces are established with
relation to any public-use heliport:
(1) Heliport primary surface: the area of the primary surface
coincides in size and shape with the designated takeoff and
landing area of a heliport. This surface is a horizontal plane at the
elevation of the established heliport elevation.
(2) Heliport approach surface: the approach surface begins at
each end of the heliport primary surface with the same width as
the primary surface, and extends outward and upward for a
horizontal distance of four thousand (4,000) feet where its width
is five hundred (500) feet. The slope of the approach surface is
eight (8) to one (1) for civil heliports.
(3) Heliport transitional surfaces: these surfaces extend outward
and upward from the lateral boundaries of the heliport primary
surface and from the approach surfaces at a slope of two (2) to
one (1) for a distance of two hundred fifty (250) feet measured
horizontally from the centerline of the primary and approach
surfaces.