(a) This subpart establishes standards for determining obstructions to
air navigation. It applies to existing and proposed manmade objects,
objects of natural growth, and terrain. The standards apply to the use of
navigable airspace by aircraft and to existing air navigation facilities,
such as an air navigation aid, airport, Federal airway, instrument
approach or departure procedure, or approved off-airway route.
Additionally, they apply to a planned facility or use, or a change in an
existing facility or use, if a proposal therefor is on file with the
Federal Aviation Administration or an appropriate military service on the
date the notice required by §77.13(a) is filed.
(b) At those airports having defined runways with specially prepared
hard surfaces, the primary surface for each such runway extends 200 feet
beyond each end of the runway. At those airports having defined strips or
pathways that are used regularly for the taking off and landing of
aircraft and have been designated by appropriate authority as runways, but
do not have specially prepared hard surfaces, each end of the primary
surface for each such runway shall coincide with the corresponding end of
the runway. At those airports, excluding seaplane bases, having a defined
landing and takeoff area with no defined pathways for the landing and
taking off of aircraft, a determination shall be made as to which portions
of the landing and takeoff area are regularly used as landing and takeoff
pathways. Those pathways so determined shall be considered runways and an
appropriate primary surface as defined in §77.25(c) will be considered as
being longitudinally centered on each runway so determined, and each end
of that primary surface shall coincide with the corresponding end of that
runway.
(c) The standards in this subpart apply to the effect of construction
or alteration proposals upon an airport if, at the time of filing of the
notice required by §77.13(a), that airport is --
(1) Available for public use and is listed in the Airport Directory of
the current Airman's Information Manual or in either the Alaska or Pacific
Airman's Guide and Chart Supplement; or
(2) A planned or proposed airport or an airport under construction,
that is the subject of a notice or proposal on file with the Federal
Aviation Administration, and, except for military airports, it is clearly
indicated that that airport will be available for public use; or,
(3) An airport that is operated by an armed force of the United States.