3/21/24 

AIM 

TBL 4

−

1

−

3 

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

1 

123.450

2 

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. 

4

−

1

−

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. 

4

−

1

−

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 continuously 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 

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 

Services Available to Pilots 

4

−

1

−

9