Definitions. The following words and phrases when used in this Ordinance
shall have the meaning given to them in this Section unless the context
clearly indicates otherwise.
AIRPORT ELEVATION
The highest point of an airport's useable landing area measured
in feet above sea level. The airport elevation of the Pittsburgh International
Airport is 1,204 feet above mean sea level. The elevation of the Allegheny
County Airport is 1,250 feet above mean sea level.
AIRPORT HAZARD
Any structure or object, natural or manmade, or use of land
which obstructs the airspace required for flight or aircraft in landing
or taking off at an airport or is otherwise hazardous as defined in
14 CFR Part 77 and 74 Pa. Cons. Stat. § 5102.
AIRPORT HAZARD AREA
Any area of land or water upon which an airport hazard might
be established if not prevented as provided for in this Ordinance
and the Act 164 of 1984 (Pennsylvania Laws Relating to Aviation).
APPROACH SURFACE (ZONE)
An imaginary 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
the runway based on the planned approach. The inner edge of the approach
surface is the same width as the primary surface and expands uniformly
depending on the planned approach. The approach surface zone, as shown
on Figure 1, is derived from the approach surface.
CONICAL SURFACE (ZONE)
An imaginary surface extending outward and upward from the
periphery of the horizontal surface at a slope of twenty (20) feet
horizontally to one (1) foot vertically for a horizontal distance
of 4,000 feet. The conical surface zone, as shown on Figure 1, is based on the conical surface.
DEPARTMENT
Pennsylvania Department of Transportation.
FAA
Federal Aviation Administration of the United States Department
of Transportation.
HEIGHT
For the purpose of determining the height limits in all zones
set forth in this Ordinance, the datum shall be mean sea level elevation
unless otherwise specified.
HORIZONTAL SURFACE (ZONE)
An imaginary plane 150 feet above the established airport
elevation that is constructed by swinging arcs of various radii from
the center of the end of the primary surface and then connecting the
adjacent arc by tangent lines. The radius of each arc is based on
the planned approach. The horizontal surface zone, as shown on Figure
1, is derived from the horizontal surface.
LARGER THAN UTILITY RUNWAY
A runway that is constructed for and intended to be used
by propeller driven aircraft of greater than 12,500 pounds maximum
gross weight and jet powered aircraft.
NONCONFORMING USE
Any pre-existing structure, object of natural growth, or
use of land which is inconsistent with the provisions of this Ordinance
or any amendment thereto.
NON-PRECISION INSTRUMENT RUNWAY
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 non-precision
instrument approach procedure has been approved or planned.
OBSTRUCTION
Any structure, growth, or other object, including a mobile
object, which exceeds a limiting height set forth by this Ordinance.
PRECISION INSTRUMENT RUNWAY
A runway having an existing instrument approach procedure
utilizing an Instrument Landing System (ILS) or a Precisions Approach
Radar (PAR). It also means a runway for which a precision approach
system is planned and is so indicated on an approved airport layout
plan or any other planning document.
PRIMARY SURFACE (ZONE)
An imaginary surface longitudinally centered on the runway,
extending 200 feet beyond the end of paved runways or ending at each
end of turf runways. The elevation of any point on the primary surface
is the same as the elevation of the nearest point on the runway centerline.
The primary surface zone, as shown on Figure 1, is derived from the primary surface.
RUNWAY
A defined area of an airport prepared for landing and takeoff
of aircraft along its length.
STRUCTURE
An object, including a mobile object, constructed or installed
by man, including but without limitation, buildings, towers, cranes,
smokestacks, earth formation and overhead transmission lines.
TRANSITIONAL SURFACE (ZONE)
An imaginary surface that extends outward and upward from
the edge of the primary surface to the horizontal surface at a slope
of seven (7) feet horizontally to one (1) foot vertically (7:1). The
transitional surface zone, as shown on Figure 1, is derived from the transitional surface.
TREE
Any object of natural growth.
UTILITY RUNWAY
A runway that is constructed for and intended to be used
by propeller driven aircraft of 12,500 pounds maximum gross weight
or less.
VISUAL RUNWAY
A runway intended solely for the operation or aircraft using
visual approach procedures.