Federal Aviation Administration Twentieth Edition
8. Use of Runways/Declared Distances
8.1 Runways are identified by numbers which indicate the nearest 10.degree increment of the azimuth of the runway centerline. For example, where the magnetic azimuth is 183 degrees, the runway designation would be 18; for a magnetic azimuth of 87 degrees, the runway designation would be 9. For a magnetic azimuth ending in the number 5, such as 185, the runway designation could be either 18 or 19. Wind direction issued by the tower is also magnetic, and wind velocity is in knots.
8.2 Airport proprietors are responsible for taking the lead in local aviation noise control. Accordingly, they may propose specific noise abatement plans to the FAA. If approved, these plans are applied in the form of Formal or Informal Runway Use Programs for noise abatement purposes.
8.3 At airports where no runway use program is established, ATC clearance may specify:
8.3.1 The runway most nearly aligned with the wind when it is five knots or more.
8.3.2 The “calm wind” runway when wind is less than five knots.
8.3.3 Another runway if operationally advanta-geous.
NOTE.
It is not necessary for a controller to specifically inquire if the pilot will use a specific runway or to offer the pilot a choice of runways. If a pilot prefers to use a different runway than that specified or the one most nearly aligned with the wind, the pilot is expected to inform ATC accordingly.
8.4 At airports where a runway use program is established, ATC will assign runways deemed to have the least noise impact. If in the interest of safety a runway different than that specified is preferred, the pilot is expected to advise ATC accordingly. ATC will honor such requests and advise pilots when the requested runway is noise sensitive. When use of a runway other that the one assigned is requested, pilot cooperation is encouraged to preclude disruption of traffic flows or creation of conflicting patterns.
8.5 Declared Distances.
8.5.1 Declared distances for a runway represent the maximum distances available and suitable for meeting takeoff and landing distance performance requirements. These distances are determined in accordance with FAA runway design standards by adding to the physical length of paved runway any clearway or stopway and subtracting from that sum any lengths necessary to obtain the standard runway safety areas, runway object free areas, or runway protection zones. As a result of these additions and subtractions, the declared distances for a runway may be more or less than the physical length of the runway as depicted on aeronautical charts and related publications, or available in electronic navigation databases provided by either the U.S. Government or commercial companies.
8.5.2 All 14 CFR Part 139 airports report declared distances for each runway. Other airports may also report declared distances for a runway if necessary to meet runway design standards or to indicate the presence of a clearway or stopway. Where reported, declared distances for each runway end are published in the Airport/Facility Directory (A/FD). For runways without published declared distances, the declared distances may be assumed to be equal to the physical length of the runway unless there is a displaced landing threshold, in which case the Landing Distance Available (LDA) is shortened by the amount of the threshold displacement.
NOTE.
A symbol
is shown on U.S. Government charts to indicate that runway declared distance information is available (See appropriate A/FD, Alaska, or Pacific Supplement).
8.5.2.1 The FAA uses the following definitions for runway declared distances (See FIG ENR 1.1.4).
REFERENCE.
Pilot/Controller Glossary Terms: “Accelerate.Stop Distance Available,” “Landing Distance Available,” “Takeoff Distance Available,” “Takeoff Run Available,” ” Stopway,” and “Clearway.”
a) Takeoff Run Available (TORA) – The runway length declared available and suitable for the ground run of an airplane taking off.
The TORA is typically the physical length of the run-way, but it may be shorter than the runway length if necessary to satisfy runway design standards. For ex-ample, the TORA may be shorter than the runway length if a portion of the runway must be used to satis-fy runway protection zone requirements.
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：美国航行情报汇编 AERONAUTICAL INFORMATION PUBLICATION AIP 2(21)
