Aeronautical Information Manual
AIM 4-1-9
Traffic Advisory Practices at Airports Without Operating Control Towers
(See TBL 4-1-1 .)
Airport Operations Without Operating Control Tower 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; and
Pilots use the correct airport name, as identified in appropriate aeronautical publications, to reduce the risk of confusion when communicating their position, intentions, and/or exchanging traffic information.
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. NOTE-
FSS airport advisories are available only in Alaska.
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 and approach charts.
Communicating on a Common Frequency 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. NOTE-
FSS frequencies are available only in Alaska.
TBL 4-1-9 Summary of Recommended Communication Procedures Communication/Broadcast Procedures
Facility at Airport
Frequency Use
Outbound
Inbound
Practice Instrument Approach
1.
UNICOM (No Tower or FSS)
Communicate with UNICOM station on published CTAF frequency (122.7; 122.8; 122.725; 122.975; or 123.0). If unable to contact UNICOM station, use self‐announce procedures on CTAF.
Before taxiing and before taxiing on the runway for departure.
10 miles out. Entering downwind, base, and final. Leaving the runway.
2.
No Tower, FSS, or UNICOM
Self‐announce on MULTICOM frequency 122.9.
Before taxiing and before taxiing on the runway for departure.
10 miles out. Entering downwind, base, and final. Leaving the runway.
Departing final approach fix (name) or on final approach segment inbound.
3.
No Tower in operation, FSS open (Alaska only)
Communicate with FSS on CTAF frequency.
Before taxiing and before taxiing on the runway for departure.
10 miles out. Entering downwind, base, and final. Leaving the runway.
Approach completed/terminated.
4.
FSS Closed (No Tower)
Self‐announce on CTAF.
Before taxiing and before taxiing on the runway for departure.
10 miles out. Entering downwind, base, and final. Leaving the runway.
5.
Tower or FSS not in operation
Self‐announce on CTAF.
Before taxiing and before taxiing on the runway for departure.
10 miles out. Entering downwind, base, and final. Leaving the runway.
6.
Designated CTAF Area (Alaska Only)
Self‐announce on CTAF designated on chart or Chart Supplement Alaska.
Before taxiing and before taxiing on the runway for departure until leaving designated area.
When entering designated CTAF area.
CTAF (Alaska Only) . In Alaska, a CTAF may also be designated for the purpose of carrying out advisory practices while operating in designated areas with a high volume of VFR traffic.
The CTAF frequency for a particular airport or area is contained in the Chart Supplement U.S., Chart Supplement Alaska, Alaska Terminal Publication, Instrument Approach Procedure Charts, and Instrument Departure Procedure (DP) Charts. Also, the CTAF frequency can be obtained by contacting any FSS. Use of the appropriate CTAF, combined with a visual alertness and application of the following recommended good operating practices, will enhance safety of flight into and out of all uncontrolled airports.
Recommended Traffic Advisory Practices Pilots of inbound traffic should monitor and communicate as appropriate on the designated CTAF from 10 miles to landing. Pilots of departing aircraft should monitor/communicate on the appropriate frequency from start‐up, during taxi, and until 10 miles from the airport unless the CFRs or local procedures require otherwise.
Pilots of aircraft conducting other than arriving or departing operations at altitudes normally used by arriving and departing aircraft should monitor/communicate on the appropriate frequency while within 10 miles of the airport unless required to do otherwise by the CFRs or local procedures. Such operations include parachute jumping/dropping, en route, practicing maneuvers, etc.
In Alaska, pilots of aircraft conducting other than arriving or departing operations in designated CTAF areas should monitor/communicate on the appropriate frequency while within the designated area, unless required to do otherwise by CFRs or local procedures. Such operations include parachute jumping/dropping, en route, practicing maneuvers, etc. REFERENCE-
AIM, Para 3-5-4 , Parachute Jump Aircraft Operations
Airport Advisory/Information Services Provided by a FSS There are two advisory type services provided at selected airports. Local Airport Advisory (LAA) is available only in Alaska and provided at airports that have a FSS physically located on the airport, which does not have a control tower or where the tower is operated on a part-time basis. The CTAF for LAA airports is disseminated in the appropriate aeronautical publications.
Remote Airport Information Service (RAIS) is provided in support of special events at nontowered airports by request from the airport authority.
In communicating with a CTAF FSS, check the airport's automated weather and establish two-way communications before transmitting outbound/inbound intentions or information. An inbound aircraft should initiate contact approximately 10 miles from the airport, reporting aircraft identification and type, altitude, location relative to the airport, intentions (landing or over flight), possession of the automated weather, and request airport advisory or airport information service. A departing aircraft should initiate contact before taxiing, reporting aircraft identification and type, VFR or IFR, location on the airport, intentions, direction of take-off, possession of the automated weather, and request airport advisory or information service. Also, report intentions before taxiing onto the active runway for departure. If you must change frequencies for other service after initial report to FSS, return to FSS frequency for traffic update. Inbound EXAMPLE-
Vero Beach radio, Centurion Six Niner Delta Delta is ten miles south, two thousand, landing Vero Beach. I have the automated weather, request airport advisory.
Outbound EXAMPLE-
Vero Beach radio, Centurion Six Niner Delta Delta, ready to taxi to runway 22, VFR, departing to the southwest. I have the automated weather, request airport advisory.
Airport advisory service includes wind direction and velocity, favored or designated runway, altimeter setting, known airborne and ground traffic, NOTAMs, airport taxi routes, airport traffic pattern information, and instrument approach procedures. These elements are varied so as to best serve the current traffic situation. Some airport managers have specified that under certain wind or other conditions designated runways be used. Pilots should advise the FSS of the runway they intend to use. NOTE-
All aircraft in the vicinity of an airport may not be in communication with the FSS.
Information Provided by Aeronautical Advisory Stations (UNICOM) UNICOM is a nongovernment air/ground radio communication station which may provide airport information at public use airports where there is no tower or FSS.
On pilot request, UNICOM stations may provide pilots with weather information, wind direction, the recommended runway, or other necessary information. If the UNICOM frequency is designated as the CTAF, it will be identified in appropriate aeronautical publications.
Unavailability of Information from FSS or UNICOM Should LAA by an FSS or Aeronautical Advisory Station UNICOM be unavailable, wind and weather information may be obtainable from nearby controlled airports via Automatic Terminal Information Service (ATIS) or Automated Weather Observing System (AWOS) frequency.
Self‐Announce Position and/or Intentions General. Self‐announce is a procedure whereby pilots broadcast their position or intended flight activity or ground operation on the designated CTAF. This procedure is used primarily at airports which do not have an FSS on the airport. The self‐announce procedure should also be used if a pilot is unable to communicate with the FSS on the designated CTAF. Pilots stating, “Traffic in the area, please advise” is not a recognized Self-Announce Position and/or Intention phrase and should not be used under any condition.
If an airport has a tower and it is temporarily closed, or operated on a part‐time basis and there is no FSS on the airport or the FSS is closed, use the CTAF to self‐announce your position or intentions.
Where there is no tower, FSS, or UNICOM station on the airport, use MULTICOM frequency 122.9 for self‐announce procedures. Such airports will be identified in appropriate aeronautical information publications.
Straight-in Landings. The FAA discourages VFR straight-in approaches to landings due to the increased risk of a mid-air collision. However, if a pilot chooses to execute a straight-in approach for landing without entering the airport traffic pattern, the pilot should self-announce their position on the designated CTAF approximately 8 to 10 miles from the airport and coordinate their straight-in approach and landing with other airport traffic. Pilots executing a straight-in approach (IFR or VFR) do not have priority over other aircraft in the traffic pattern, and must comply with the provisions of 14 CFR 91.113 (g), Right-of-way rules.
Traffic Pattern Operations. All traffic within a 10-mile radius of a non-towered airport or a part-time-towered airport when the control tower is not operating, should monitor and communicate on the designated CTAF when entering the traffic pattern. Pilots operating in the traffic pattern or on a straight-in approach must be alert at all times to other aircraft in the pattern, or conducting straight-in approaches, and communicate their position to avoid a possible traffic conflict. In the airport traffic pattern and while on straight-in approaches to a runway, effective communication and a pilot's responsibility to see-and-avoid are essential mitigations to avoid a possible midair collision. In addition, following established traffic pattern procedures eliminates excessive maneuvering at low altitudes, reducing the risk of loss of aircraft control. REFERENCE-
FAA Advisory Circular (AC) 90-66, Non-Towered Airport Flight Operations.
Practice Approaches. Pilots conducting practice instrument approaches should be particularly alert for other aircraft that may be departing in the opposite direction. When conducting any practice approach, regardless of its direction relative to other airport operations, pilots should make announcements on the CTAF as follows: Departing the final approach fix, inbound (nonprecision approach) or departing the outer marker or fix used in lieu of the outer marker, inbound (precision approach);
Established on the final approach segment or immediately upon being released by ATC;
Upon completion or termination of the approach; and
Upon executing the missed approach procedure.
Departing aircraft should always be alert for arrival aircraft coming from the opposite direction.
Recommended self-announce broadcasts: It should be noted that aircraft operating to or from another nearby airport may be making self-announce broadcasts on the same UNICOM or MULTICOM frequency. To help identify one airport from another, the airport name should be spoken at the beginning and end of each self-announce transmission. When referring to a specific runway, pilots should use the runway number and not use the phrase “Active Runway.” Inbound EXAMPLE-
Strawn traffic, Apache Two Two Five Zulu, (position), (altitude), (descending) or entering downwind/base/final (as appropriate) runway one seven full stop, touch-and-go, Strawn.
Strawn traffic Apache Two Two Five Zulu clear of runway one seven Strawn.
Outbound EXAMPLE-
Strawn traffic, Queen Air Seven One Five Five Bravo (location on airport) taxiing to runway two six Strawn.
Strawn traffic, Queen Air Seven One Five Five Bravo departing runway two six. Departing the pattern to the (direction), climbing to (altitude) Strawn.
Practice Instrument Approach EXAMPLE-
Strawn traffic, Cessna Two One Four Three Quebec (position from airport) inbound descending through (altitude) practice (name of approach) approach runway three five Strawn.
Strawn traffic, Cessna Two One Four Three Quebec practice (type) approach completed or terminated runway three five Strawn.
UNICOM Communications Procedures In communicating with a UNICOM station, the following practices will help reduce frequency congestion, facilitate a better understanding of pilot intentions, help identify the location of aircraft in the traffic pattern, and enhance safety of flight: Select the correct UNICOM frequency.
State the identification of the UNICOM station you are calling in each transmission.
Speak slowly and distinctly.
Report approximately 10 miles from the airport, reporting altitude, and state your aircraft type, aircraft identification, location relative to the airport, state whether landing or overflight, and request wind information and runway in use.
Report on downwind, base, and final approach.
Report leaving the runway.
Recommended UNICOM phraseologies: Inbound PHRASEOLOGY-
FREDERICK UNICOM CESSNA EIGHT ZERO ONE TANGO FOXTROT 10 MILES SOUTHEAST DESCENDING THROUGH (altitude) LANDING FREDERICK, REQUEST WIND AND RUNWAY INFORMATION FREDERICK.
FREDERICK TRAFFIC CESSNA EIGHT ZERO ONE TANGO FOXTROT ENTERING DOWNWIND/BASE/ FINAL (as appropriate) FOR RUNWAY ONE NINER (full stop/touch-and-go) FREDERICK.
FREDERICK TRAFFIC CESSNA EIGHT ZERO ONE TANGO FOXTROT CLEAR OF RUNWAY ONE NINER FREDERICK.
Outbound PHRASEOLOGY-
FREDERICK UNICOM CESSNA EIGHT ZERO ONE TANGO FOXTROT (location on airport) TAXIING TO RUNWAY ONE NINER, REQUEST WIND AND TRAFFIC INFORMATION FREDERICK.
FREDERICK TRAFFIC CESSNA EIGHT ZERO ONE TANGO FOXTROT DEPARTING RUNWAY ONE NINER. “REMAINING IN THE PATTERN” OR “DEPARTING THE PATTERN TO THE (direction) (as appropriate)” FREDERICK.
Retrieved from ecfr.gov on July 20, 2026.