AIM
4/3/14
4−3−16
Airport Operations
b.
Although the traffic signal light offers the
advantage that some control may be exercised over
nonradio equipped aircraft, pilots should be cogni-
zant of the disadvantages which are:
1.
Pilots may not be looking at the control tower
at the time a signal is directed toward their aircraft.
2.
The directions transmitted by a light signal
are very limited since only approval or disapproval of
a pilot’s anticipated actions may be transmitted. No
supplement or explanatory information may be
transmitted except by the use of the “General
Warning Signal” which advises the pilot to be on the
alert.
c.
Between sunset and sunrise, a pilot wishing to
attract the attention of the control tower should turn
on a landing light and taxi the aircraft into a position,
clear of the active runway, so that light is visible to the
tower. The landing light should remain on until
appropriate signals are received from the tower.
d.
Air Traffic Control Tower Light Gun Signals.
e.
During daylight hours, acknowledge tower
transmissions or light signals by moving the ailerons
or rudder. At night, acknowledge by blinking the
landing or navigation lights. If radio malfunction
occurs after departing the parking area, watch the
tower for light signals or monitor tower frequency.
TBL 4
−3−1
Air Traffic Control Tower Light Gun Signals
Meaning
Color and Type of Signal
Movement of Vehicles,
Equipment and Personnel
Aircraft on the Ground
Aircraft in Flight
Steady green
Cleared to cross, proceed or go
Cleared for takeoff
Cleared to land
Flashing green
Not applicable
Cleared for taxi
Return for landing (to be
followed by steady green at the
proper time)
Steady red
STOP
STOP
Give way to other aircraft and
continue circling
Flashing red
Clear the taxiway/runway
Taxi clear of the runway in use
Airport unsafe, do not land
Flashing white
Return to starting point on airport Return to starting point on airport Not applicable
Alternating red and green
Exercise extreme caution
Exercise extreme caution
Exercise extreme caution
4
−
3
−
14. Communications
a.
Pilots of departing aircraft should communicate
with the control tower on the appropriate ground
control/clearance delivery frequency prior to starting
engines to receive engine start time, taxi and/or
clearance information. Unless otherwise advised by
the tower, remain on that frequency during taxiing
and runup, then change to local control frequency
when ready to request takeoff clearance.
NOTE
−
Pilots are encouraged to monitor the local tower frequency
as soon as practical consistent with other ATC
requirements.
REFERENCE
−
AIM, Automatic Terminal Information Service (ATIS),
Paragraph 4
b.
The tower controller will consider that pilots of
turbine−powered aircraft are ready for takeoff when
they reach the runway or warm−up block unless
advised otherwise.
c.
The majority of ground control frequencies are
in the 121.6−121.9 MHz bandwidth. Ground control
frequencies are provided to eliminate frequency
congestion on the tower (local control) frequency and
are limited to communications between the tower and
aircraft on the ground and between the tower and
utility vehicles on the airport, provide a clear VHF
channel for arriving and departing aircraft. They are
used for issuance of taxi information, clearances, and
other necessary contacts between the tower and
aircraft or other vehicles operated on the airport. A
pilot who has just landed should not change from the
tower frequency to the ground control frequency until
directed to do so by the controller. Normally, only one
ground control frequency is assigned at an airport;
however, at locations where the amount of traffic so
warrants, a second ground control frequency and/or
another frequency designated as a clearance delivery
frequency, may be assigned.