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6/17/21 

AIM 

TBL 4

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Other Frequency Usage Designated by FCC 

Use 

Frequency 

Air-to-air communication 
(private fixed wing aircraft). 

122.750 

Helicopter air

to

air 

communications; air traffic control 
operations. 

123.025 

Aviation instruction, Glider, Hot Air 
Balloon 

(not to be used for 

advisory service)

123.300 
123.500 

Assignment to flight test land and 
aircraft stations (not for air

to

air 

communication except for those 
aircraft operating in an oceanic 
FIR). 

123.400

123.450

1

This frequency is available only to itinerant stations that 

have a requirement to be periodically transferred to various 
locations. 

2

Mobile station operations on these frequencies are limited 

to an area within 320 km (200 mi) of an associated flight 
test land station. 

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12.  Use of UNICOM for ATC Purposes 

UNICOM service may be used for ATC purposes, 
only under the following circumstances: 

a. 

Revision to proposed departure time. 

b. 

Takeoff, arrival, or flight plan cancellation 

time. 

c. 

ATC clearance, provided arrangements are 

made between the ATC facility and the UNICOM 
licensee to handle such messages. 

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13.  Automatic Terminal Information 

Service (ATIS) 

a. 

ATIS is the continuous broadcast of recorded 

noncontrol information in selected high activity 
terminal areas. Its purpose is to improve controller 
effectiveness and to relieve frequency congestion by 
automating the repetitive transmission of essential 
but routine information. The information is continu-
ously broadcast over a discrete VHF radio frequency 
or the voice portion of a local NAVAID. Arrival ATIS 
transmissions on a discrete VHF radio frequency are 
engineered according to the individual facility 
requirements, which would normally be a protected 
service volume of 20 NM to 60 NM from the ATIS 
site and a maximum altitude of 25,000 feet AGL. In 

the case of a departure ATIS, the protected service 
volume cannot exceed 5 NM and 100 feet AGL. At 
most locations, ATIS signals may be received on the 
surface of the airport, but local conditions may limit 
the maximum ATIS reception distance and/or 
altitude. Pilots are urged to cooperate in the ATIS 
program as it relieves frequency congestion on 
approach control, ground control, and local control 
frequencies. The Chart Supplement U.S. indicates 
airports for which ATIS is provided. 

b. 

ATIS information includes: 

1. 

Airport/facility name 

2. 

Phonetic letter code 

3. 

Time of the latest weather sequence (UTC) 

4. 

Weather information consisting of: 

(a) 

Wind direction and velocity 

(b) 

Visibility 

(c) 

Obstructions to vision 

(d) 

Present weather consisting of: sky condi-

tion, temperature, dew point, altimeter, a density 
altitude advisory when appropriate, and other 
pertinent remarks included in the official weather 
observation 

5. 

Instrument approach and runway in use. 

The ceiling/sky condition, visibility, and obstructions 
to vision may be omitted from the ATIS broadcast if 
the ceiling is above 5,000 feet and the visibility is 
more than 5 miles. The departure runway will only be 
given if different from the landing runway except at 
locations having a separate ATIS for departure. The 
broadcast may include the appropriate frequency and 
instructions for VFR arrivals to make initial contact 
with approach control. Pilots of aircraft arriving or 
departing the terminal area can receive the 
continuous ATIS broadcast at times when cockpit 
duties are least pressing and listen to as many repeats 
as desired. ATIS broadcast must be updated upon the 
receipt of any official hourly and special weather. A 
new recording will also be made when there is a 
change in other pertinent data such as runway change, 
instrument approach in use, etc. 

EXAMPLE

 

Dulles International information Sierra. One four zero 
zero zulu. Wind three five zero at eight. Visibility one zero. 
Ceiling four thousand five hundred broken. Temperature 
three four. Dew point two eight. Altimeter three zero one 
zero. ILS runway one right approach in use. Departing 

Services Available to Pilots 

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