4/20/23 

AIM 

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 

Services Available to Pilots 

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