AIM

4/20/23

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Services Available to Pilots

Chapter 4. Air Traffic Control

Section 1. Services Available to Pilots

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1. Air Route Traffic Control Centers

Centers are established primarily to provide air traffic service to aircraft operating on IFR flight plans within
controlled airspace, and principally during the en route phase of flight.

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2. Control Towers

Towers have been established to provide for a safe, orderly and expeditious flow of traffic on and in the vicinity
of an airport. When the responsibility has been so delegated, towers also provide for the separation of IFR aircraft
in the terminal areas.

REFERENCE

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AIM, Para 5

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3, Approach Control.

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3. Flight Service Stations

Flight Service Stations (FSSs) are air traffic facilities that provide pilot briefings, flight plan processing, en route
flight advisories, search and rescue services, and assistance to lost aircraft and aircraft in emergency situations.
FSSs also relay ATC clearances, process Notices to Air Missions, and broadcast aviation weather and
aeronautical information. In Alaska, designated FSSs also take weather observations, and provide Airport
Advisory Services (AAS).

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4. Recording and Monitoring

a.

Calls to air traffic control (ATC) facilities (ARTCCs, Towers, FSSs, Central Flow, and Operations Centers)

over radio and ATC operational telephone lines (lines used for operational purposes such as controller
instructions, briefings, opening and closing flight plans, issuance of IFR clearances and amendments, counter
hijacking activities, etc.) may be monitored and recorded for operational uses such as accident investigations,
accident prevention, search and rescue purposes, specialist training and evaluation, and technical evaluation and
repair of control and communications systems.

b.

Where the public access telephone is recorded, a beeper tone is not required. In place of the “beep” tone

the FCC has substituted a mandatory requirement that persons to be recorded be given notice they are to be
recorded and give consent. Notice is given by this entry, consent to record is assumed by the individual placing
a call to the operational facility.

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5. Communications Release of IFR Aircraft Landing at an Airport Without an Operating

Control Tower

Aircraft operating on an IFR flight plan, landing at an airport without an operating control tower will be advised
to change to the airport advisory frequency when direct communications with ATC are no longer required.
Towers and centers do not have nontower airport traffic and runway in use information. The instrument approach
may not be aligned with the runway in use; therefore, if the information has not already been obtained, pilots
should make an expeditious change to the airport advisory frequency when authorized.

REFERENCE

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AIM, Para 5

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4, Advance Information on Instrument Approach.

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6. Pilot Visits to Air Traffic Facilities

Pilots are encouraged to participate in local pilot/air traffic control outreach activities. However, due to security
and workload concerns, requests for air traffic facility visits may not always be approved. Therefore, visit