AIM
4/3/14
4−1−6
Services Available to Pilots
4
−
1
−
10. IFR Approaches/Ground Vehicle
Operations
a. IFR Approaches.
When operating in accor-
dance with an IFR clearance and ATC approves a
change to the advisory frequency, make an
expeditious change to the CTAF and employ the
recommended traffic advisory procedures.
b. Ground Vehicle Operation.
Airport ground
vehicles equipped with radios should monitor the
CTAF frequency when operating on the airport
movement area and remain clear of runways/taxi-
ways being used by aircraft. Radio transmissions
from ground vehicles should be confined to
safety-related matters.
c. Radio Control of Airport Lighting Systems.
Whenever possible, the CTAF will be used to control
airport lighting systems at airports without operating
control towers. This eliminates the need for pilots to
change frequencies to turn the lights on and allows a
continuous listening watch on a single frequency. The
CTAF is published on the instrument approach chart
and in other appropriate aeronautical information
publications. For further details concerning radio
controlled lights, see AC 150/5340−27, Air−to−
Ground Radio Control of Airport Lighting Systems.
4
−
1
−
11. Designated UNICOM/MULTICOM
Frequencies
Frequency use
a.
The following listing depicts UNICOM and
MULTICOM frequency uses as designated by the
Federal Communications Commission (FCC).
TBL 4
−1−2
Unicom/Multicom Frequency Usage
Use
Frequency
Airports without an operating
control tower.
122.700
122.725
122.800
122.975
123.000
123.050
123.075
(MULTICOM FREQUENCY)
Activities of a temporary, seasonal,
emergency nature or search and
rescue, as well as, airports with no
tower, FSS, or UNICOM.
122.900
(MULTICOM FREQUENCY)
Forestry management and fire
suppression, fish and game
management and protection, and
environmental monitoring and
protection.
122.925
Airports with a control tower or
FSS on airport.
122.950
NOTE
−
1. In some areas of the country, frequency interference
may be encountered from nearby airports using the same
UNICOM frequency. Where there is a problem, UNICOM
operators are encouraged to develop a “least interfer-
ence” frequency assignment plan for airports concerned
using the frequencies designated for airports without
operating control towers. UNICOM licensees are
encouraged to apply for UNICOM 25 kHz spaced channel
frequencies. Due to the extremely limited number of
frequencies with 50 kHz channel spacing, 25 kHz channel
spacing should be implemented. UNICOM licensees may
then request FCC to assign frequencies in accordance with
the plan, which FCC will review and consider for approval.
2. Wind direction and runway information may not be
available on UNICOM frequency 122.950.
b.
The following listing depicts other frequency
uses as designated by the Federal Communications
Commission (FCC). (See TBL 4−1−3.)