Aeronautical Information Manual (AIM), page 174

Index   173 -- Page 174 -- 175


4-1-7. Operation Take-off and Operation
Operation Take-off is a program that educates pilots
in how best to utilize the FSS modernization efforts
and services available in Flight Service Stations
(FSS), as stated in FAA Order 7230.17, Pilot
Education Program - Operation Takeoff. Operation
Raincheck is a program designed to familiarize pilots
with the ATC system, its functions, responsibilities
and benefits.

4-1-8. Approach Control Service for VFR
Arriving Aircraft
a. Numerous approach control facilities have
established programs for arriving VFR aircraft to
contact approach control for landing information.
This information includes: wind, runway, and
altimeter setting at the airport of intended landing.
This information may be omitted if contained in the
Automatic Terminal Information Service (ATIS)
broadcast and the pilot states the appropriate ATIS
Pilot use of "have numbers" does not indicate receipt of the
ATIS broadcast. In addition, the controller will provide
traffic advisories on a workload permitting basis.
b. Such information will be furnished upon initial
contact with concerned approach control facility. The
pilot will be requested to change to the tower
frequency at a predetermined time or point, to receive
further landing information.
c. Where available, use of this procedure will not
hinder the operation of VFR flights by requiring
excessive spacing between aircraft or devious
d. Compliance with this procedure is not

mandatory but pilot participation is encouraged.

AIM, Paragraph 4-1-18 , Terminal Radar Services for VFR Aircraft

Approach control services for VFR aircraft are normally
dependent on ATC radar. These services are not available
during periods of a radar outage. Approach control
services for VFR aircraft are limited when CENRAP is in

4-1-9. Traffic Advisory Practices at
Airports Without Operating Control Towers

(See TBL 4-1-1.)


a. Airport Operations Without Operating
Control Tower
1. There is no substitute for alertness while in
the vicinity of an airport. It is essential that pilots be
alert and look for other traffic and exchange traffic
information when approaching or departing an
airport without an operating control tower. This is of
particular importance since other aircraft may not
have communication capability or, in some cases,
pilots may not communicate their presence or
intentions when operating into or out of such airports.
To achieve the greatest degree of safety, it is essential
that all radio-equipped aircraft transmit/receive on a
common frequency identified for the purpose of
airport advisories.
2. An airport may have a full or part-time tower
or FSS located on the airport, a full or part-time
UNICOM station or no aeronautical station at all.
There are three ways for pilots to communicate their
intention and obtain airport/traffic information when
operating at an airport that does not have an operating
tower: by communicating with an FSS, a UNICOM
operator, or by making a self-announce broadcast.

FSS airport advisories are available only in Alaska.
3. Many airports are now providing completely
automated weather, radio check capability and airport
advisory information on an automated UNICOM
system. These systems offer a variety of features,
typically selectable by microphone clicks, on the
UNICOM frequency. Availability of the automated
UNICOM will be published in the Chart Supplement
U.S. and approach charts.
b. Communicating on a Common Frequency

1. The key to communicating at an airport

without an operating control tower is selection of the

correct common frequency. The acronym CTAF

which stands for Common Traffic Advisory
Frequency, is synonymous with this program. A
CTAF is a frequency designated for the purpose of
carrying out airport advisory practices while
operating to or from an airport without an operating
control tower. The CTAF may be a UNICOM,
MULTICOM, FSS, or tower frequency and is
identified in appropriate aeronautical publications.

FSS frequencies are available only in Alaska.

4-1-2 Services Available to Pilots

Page 174 of the Aeronautical Information Manual (AIM.pdf)
AIM: Official Guide to Basic Flight Information and ATC Procedures

Index   173 -- Page 174 -- 175