AIM

4/3/14

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Airport Operations

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5. Unexpected Maneuvers in the

Airport Traffic Pattern

There have been several incidents in the vicinity of

controlled airports that were caused primarily by

aircraft executing unexpected maneuvers. ATC

service is based upon observed or known traffic and

airport conditions. Controllers establish the sequence

of arriving and departing aircraft by requiring them to

adjust flight as necessary to achieve proper spacing.

These adjustments can only be based on observed

traffic, accurate pilot reports, and anticipated aircraft

maneuvers. Pilots are expected to cooperate so as to

preclude disrupting traffic flows or creating

conflicting patterns. The pilot−in−command of an

aircraft is directly responsible for and is the final

authority as to the operation of the aircraft. On

occasion it may be necessary for pilots to maneuver

their aircraft to maintain spacing with the traffic they

have been sequenced to follow. The controller can

anticipate minor maneuvering such as shallow “S”

turns. The controller cannot, however, anticipate a

major maneuver such as a 360 degree turn. If a pilot

makes a 360 degree turn after obtaining a landing

sequence, the result is usually a gap in the landing

interval and, more importantly, it causes a chain

reaction which may result in a conflict with following

traffic and an interruption of the sequence established

by the tower or approach controller. Should a pilot

decide to make maneuvering turns to maintain

spacing behind a preceding aircraft, the pilot should

always advise the controller if at all possible. Except

when requested by the controller or in emergency

situations, a 360 degree turn should never be executed

in the traffic pattern or when receiving radar service

without first advising the controller.

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6. Use of Runways/Declared Distances

a.

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.

b.

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.

REFERENCE

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Pilot/Controller Glossary Term

− “Runway Use Program”

1.

At airports where no runway use program is

established, ATC clearances may specify:

(a)

The runway most nearly aligned with the

wind when it is 5 knots or more;

(b)

The “calm wind” runway when wind is

less than 5 knots; or

(c)

Another runway if operationally advanta-

geous.

NOTE

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It is not necessary for a controller to specifically inquire if
the pilot will use a specific runway or to offer a choice of
runways. If a pilot prefers to use a different runway from
that specified, or the one most nearly aligned with the wind,
the pilot is expected to inform ATC accordingly.

2.

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 from 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 than the one assigned is requested, pilot

cooperation is encouraged to preclude disruption of

traffic flows or the creation of conflicting patterns.

c. Declared Distances.

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.

2.

All 14 CFR Part 139 airports report declared

distances for each runway. Other airports may also