Radio communications are a critical link in
the ATC system. The link can be a strong bond between
pilot and controller or it can be broken with surprising
speed and disastrous results. Discussion herein provides
basic procedures for new pilots and also highlights safe
operating concepts for all pilots.
The single, most important thought in
pilot-controller communications is understanding. It is
essential, therefore, that pilots acknowledge each radio
communication with ATC by using the appropriate aircraft
call sign. Brevity is important, and contacts should be
kept as brief as possible, but controllers must know what
you want to do before they can properly carry out their
control duties. And you, the pilot, must know exactly what
the controller wants you to do. Since concise phraseology
may not always be adequate, use whatever words are
necessary to get your message across. Pilots are to
maintain vigilance in monitoring air traffic control radio
communications frequencies for potential traffic conflicts
with their aircraft especially when operating on an active
runway and/or when conducting a final approach to landing.
All pilots will find the Pilot/Controller
Glossary very helpful in learning what certain words or
phrases mean. Good phraseology enhances safety and is the
mark of a professional pilot. Jargon, chatter, and "CB"
slang have no place in ATC communications. The
Pilot/Controller Glossary is the same glossary used in FAA
Order 7110.65, Air Traffic Control. We recommend
that it be studied and reviewed from time to time to
sharpen your communication skills.
before you transmit. Many times you can get the
information you want through ATIS or by monitoring the
frequency. Except for a few situations where some
frequency overlap occurs, if you hear someone else
talking, the keying of your transmitter will be futile and
you will probably jam their receivers causing them to
repeat their call. If you have just changed frequencies,
pause, listen, and make sure the frequency is clear.
before keying your transmitter. Know what you want to say
and if it is lengthy; e.g., a flight plan or IFR position
report, jot it down.
The microphone should be very close to your
lips and after pressing the mike button, a slight pause
may be necessary to be sure the first word is transmitted.
Speak in a normal, conversational tone.
When you release the button, wait a few
seconds before calling again. The controller or FSS
specialist may be jotting down your number, looking for
your flight plan, transmitting on a different frequency,
or selecting the transmitter for your frequency.
Be alert to the sounds or the lack of
sounds in your receiver. Check your volume, recheck
your frequency, and make sure that your microphone is
not stuck in the transmit position. Frequency blockage
can, and has, occurred for extended periods of time due to
unintentional transmitter operation. This type of
interference is commonly referred to as a "stuck mike,"
and controllers may refer to it in this manner when
attempting to assign an alternate frequency. If the
assigned frequency is completely blocked by this type of
interference, use the procedures described for en route
IFR radio frequency outage to establish or reestablish
communications with ATC.
Be sure that you are within the performance
range of your radio equipment and the ground station
equipment. Remote radio sites do not always transmit and
receive on all of a facility's available frequencies,
particularly with regard to VOR sites where you can hear
but not reach a ground station's receiver. Remember that
higher altitudes increase the range of VHF "line of sight"
a. Initial Contact.
The terms initial contact or
initial callup means the first radio call you make
to a given facility or the first call to a different
controller or FSS specialist within a facility. Use the
Name of the facility being called;
Your full aircraft
identification as filed in the flight plan or as
discussed in paragraph
4-2-4, Aircraft Call Signs;
The type of message to follow or your
request if it is short; and
The word "Over" if required.
1. "New York
radio, Mooney Three One One Echo."
2. "Columbia ground, Cessna Three One
Six Zero Foxtrot, I-F-R Memphis."
3. "Miami center, Baron Five Six Three
Hotel, request V-F-R traffic advisories."
Many FSS's are equipped with Remote
Communications Outlets (RCO's) and can transmit on the
same frequency at more than one location. The
frequencies available at specific locations are
indicated on charts above FSS communications boxes. To
enable the specialist to utilize the correct
transmitter, advise the location and the frequency on
which you expect a reply.
St. Louis FSS can transmit on frequency 122.3 at either
Farmington, Missouri, or Decatur, Illinois, if you are
in the vicinity of Decatur, your callup should be "Saint
Louis radio, Piper Six Niner Six Yankee, receiving
Decatur One Two Two Point Three."
If radio reception is reasonably assured,
inclusion of your request, your position or altitude,
and the phrase "(ATIS) Information Charlie received" in
the initial contact helps decrease radio frequency
congestion. Use discretion; do not overload the
controller with information unneeded or superfluous. If
you do not get a response from the ground station,
recheck your radios or use another transmitter, but keep
the next contact short.
"Atlanta Center, Duke Four One Romeo, request V-F-R
traffic advisories, Twenty Northwest Rome, seven
thousand five hundred, over."
b. Initial Contact When
Your Transmitting and Receiving Frequencies are Different.
If you are attempting to establish
contact with a ground station and you are receiving on a
different frequency than that transmitted, indicate the
VOR name or the frequency on which you expect a reply.
Most FSS's and control facilities can transmit on
several VOR stations in the area. Use the appropriate
FSS call sign as indicated on charts.
New York FSS transmits on the Kennedy, the Hampton, and
the Calverton VORTAC's. If you are in the Calverton
area, your callup should be "New York radio, Cessna
Three One Six Zero Foxtrot, receiving Calverton V-O-R,
If the chart indicates FSS frequencies
above the VORTAC or in the FSS communications boxes,
transmit or receive on those frequencies nearest your
When unable to establish contact and you
wish to call any ground station, use the phrase
"ANY RADIO (tower) (station), GIVE CESSNA THREE ONE SIX
ZERO FOXTROT A CALL ON (frequency) OR (V-O-R)." If an
emergency exists or you need assistance, so state.
c. Subsequent Contacts
and Responses to Callup from a Ground Facility.
Use the same format as used
for the initial contact except you should state your
message or request with the callup in one transmission.
The ground station name and the word "Over" may be omitted
if the message requires an obvious reply and there is no
possibility for misunderstandings. You should
acknowledge all callups or clearances unless the
controller or FSS specialist advises otherwise. There are
some occasions when controllers must issue time-critical
instructions to other aircraft, and they may be in a
position to observe your response, either visually or on
radar. If the situation demands your response, take
appropriate action or immediately advise the facility of
any problem. Acknowledge with your aircraft
identification, either at the beginning or at the end of
your transmission, and one of the words "Wilco," "Roger,"
"Affirmative," "Negative," or other appropriate remarks;
e.g., "PIPER TWO ONE FOUR LIMA, ROGER." If you have been
receiving services; e.g., VFR traffic advisories and you
are leaving the area or changing frequencies, advise the
ATC facility and terminate contact.
d. Acknowledgement of
When advised by ATC to change
frequencies, acknowledge the instruction. If you select
the new frequency without an acknowledgement, the
controller's workload is increased because there is no
way of knowing whether you received the instruction or
have had radio communications failure.
At times, a controller/specialist may be
working a sector with multiple frequency assignments. In
order to eliminate unnecessary verbiage and to free the
controller/specialist for higher priority transmissions,
the controller/specialist may request the pilot
"(Identification), change to my frequency 123.4." This
phrase should alert the pilot that the
controller/specialist is only changing frequencies, not
controller/specialist, and that initial callup
phraseology may be abbreviated.
"United Two Twenty-Two on one two three point four" or
"one two three point four, United Two Twenty-Two."
e. Compliance with
When instructed by ATC to
change frequencies, select the new frequency as soon as
possible unless instructed to make the change at a
specific time, fix, or altitude. A delay in making the
change could result in an untimely receipt of important
information. If you are instructed to make the frequency
change at a specific time, fix, or altitude, monitor the
frequency you are on until reaching the specified time,
fix, or altitudes unless instructed otherwise by ATC.
AIM, ARTCC Communications, Paragraph
a. Precautions in the
Use of Call Signs.
Improper use of call signs can result in
pilots executing a clearance intended for another
aircraft. Call signs should never be abbreviated on
an initial contact or at any time when other aircraft
call signs have similar numbers/sounds or identical
letters/number; e.g., Cessna 6132F, Cessna 1622F,
Baron 123F, Cherokee 7732F, etc.
Assume that a controller issues an approach clearance to
an aircraft at the bottom of a holding stack and an
aircraft with a similar call sign (at the top of the
stack) acknowledges the clearance with the last two or
three numbers of the aircraft's call sign. If the
aircraft at the bottom of the stack did not hear the
clearance and intervene, flight safety would be
affected, and there would be no reason for either the
controller or pilot to suspect that anything is wrong.
This kind of "human factors" error can strike swiftly
and is extremely difficult to rectify.
Pilots, therefore, must be certain that
aircraft identification is complete and clearly
identified before taking action on an ATC clearance. ATC
specialists will not abbreviate call signs of air
carrier or other civil aircraft having authorized call
signs. ATC specialists may initiate abbreviated call
signs of other aircraft by using the prefix and the
last three digits/letters of the aircraft
identification after communications are established. The
pilot may use the abbreviated call sign in subsequent
contacts with the ATC specialist. When aware of
similar/identical call signs, ATC specialists will take
action to minimize errors by emphasizing certain
numbers/letters, by repeating the entire call sign, by
repeating the prefix, or by asking pilots to use a
different call sign temporarily. Pilots should use the
phrase "VERIFY CLEARANCE FOR (your complete call sign)"
if doubt exists concerning proper identity.
Civil aircraft pilots should state the
aircraft type, model or manufacturer's name, followed by
the digits/letters of the registration number. When the
aircraft manufacturer's name or model is stated, the
prefix "N" is dropped; e.g., Aztec Two Four Six Four
1. Bonanza Six Five
2. Breezy Six One Three Romeo Experimental
(omit "Experimental" after initial contact).
Air Taxi or other commercial operators
not having FAA authorized call signs should prefix
their normal identification with the phonetic word
Tango Aztec Two Four Six Four Alpha.
Air carriers and commuter air carriers
having FAA authorized call signs should identify
themselves by stating the complete call sign (using
group form for the numbers) and the word "heavy" if
2. Midwest Commuter Seven Eleven.
Military aircraft use a variety of
systems including serial numbers, word call signs, and
combinations of letters/numbers. Examples include Army
Copter 48931; Air Force 61782; REACH 31792; Pat 157; Air
Evac 17652; Navy Golf Alfa Kilo 21; Marine 4 Charlie 36,
b. Air Ambulance
Because of the priority
afforded air ambulance flights in the ATC system, extreme
discretion is necessary when using the term "LIFEGUARD."
It is only intended for those missions of an urgent
medical nature and to be utilized only for that portion of
the flight requiring expeditious handling. When requested
by the pilot, necessary notification to expedite ground
handling of patients, etc., is provided by ATC; however,
when possible, this information should be passed in
advance through non-ATC communications systems.
Civilian air ambulance flights responding
to medical emergencies (first call to an accident scene,
carrying patients, organ donors, organs, or other
urgently needed lifesaving medical material) will be
expedited by ATC when necessary. When expeditious
handling is necessary, add the word "LIFEGUARD" in the
remarks section of the flight plan. In radio
communications, use the call sign "LIFEGUARD" followed
by the aircraft registration letters/numbers.
Similar provisions have been made for the
use of "AIR EVAC" and "MED EVAC" by military air
ambulance flights, except that these military flights
will receive priority handling only when specifically
Lifeguard Two Six Four Six.
Air carrier and Air Taxi flights
responding to medical emergencies will also be expedited
by ATC when necessary. The nature of these medical
emergency flights usually concerns the transportation of
urgently needed lifesaving medical materials or vital
organs. IT IS IMPERATIVE THAT THE COMPANY/PILOT
DETERMINE, BY THE NATURE/URGENCY OF THE SPECIFIC MEDICAL
CARGO, IF PRIORITY ATC ASSISTANCE IS REQUIRED. Pilots
shall ensure that the word "LIFEGUARD" is included in
the remarks section of the flight plan and use the call
sign "LIFEGUARD" followed by the company name and flight
number for all transmissions when expeditious handling
is required. It is important for ATC to be aware of
"LIFEGUARD" status, and it is the pilot's responsibility
to ensure that this information is provided to ATC.
Lifeguard Delta Thirty-Seven.
c. Student Pilots Radio
The FAA desires to help student pilots in
acquiring sufficient practical experience in the
environment in which they will be required to operate.
To receive additional assistance while operating in
areas of concentrated air traffic, student pilots need
only identify themselves as a student pilot during their
initial call to an FAA radio facility.
Dayton tower, this is Fleetwing One Two Three Four,
This special identification will alert
FAA ATC personnel and enable them to provide student
pilots with such extra assistance and consideration as
they may need. It is recommended that student pilots
identify themselves as such, on initial contact with
each clearance delivery prior to taxiing, ground
control, tower, approach and departure control
frequency, or FSS contact.
Description of Interchange or Leased Aircraft
Controllers issue traffic information based
on familiarity with airline equipment and color/markings.
When an air carrier dispatches a flight using another
company's equipment and the pilot does not advise the
terminal ATC facility, the possible confusion in aircraft
identification can compromise safety.
Pilots flying an "interchange" or "leased"
aircraft not bearing the colors/markings of the company
operating the aircraft should inform the terminal ATC
facility on first contact the name of the operating
company and trip number, followed by the company name as
displayed on the aircraft, and aircraft type.
Air Cal Three Eleven, United (interchange/lease), Boeing
Seven Two Seven.
Ground Station Call Signs
Pilots, when calling a ground
station, should begin with the name of the facility being
called followed by the type of the facility being called as
indicated in TBL 4-2-1.
Calling a Ground Station
FAA Flight Service
FAA Flight Service
Station (En Route Flight Advisory Service (Weather))
"Seattle Flight Watch"
Airport Traffic Control
Ground Control Position
Radar or Nonradar
Approach Control Position
Radar Departure Control
"St. Louis Departure"
FAA Air Route Traffic
4-2-7. Phonetic Alphabet
The International Civil
Aviation Organization (ICAO) phonetic alphabet is used by
FAA personnel when communications conditions are such that
the information cannot be readily received without their
use. ATC facilities may also request pilots to use phonetic
letter equivalents when aircraft with similar sounding
identifications are receiving communications on the same
frequency. Pilots should use the phonetic alphabet when
identifying their aircraft during initial contact with air
traffic control facilities. Additionally, use the phonetic
equivalents for single letters and to spell out groups of
letters or difficult words during adverse communications
conditions. (See TBL 4-2-2.)
Figures indicating hundreds and thousands
in round number, as for ceiling heights, and upper wind
levels up to 9,900 shall be spoken in accordance with the
1. 500 five hundred
2. 4,500 four thousand five hundred
Numbers above 9,900 shall be spoken by
separating the digits preceding the word "thousand."
1. 10,000 one zero
2. 13,500 one three thousand five hundred
Transmit airway or jet route numbers as
1. V12 Victor Twelve
2. J533 J Five Thirty-Three
All other numbers shall be transmitted by
pronouncing each digit.
10 one zero
When a radio frequency contains a decimal
point, the decimal point is spoken as "POINT."
122.1 one two two point one
ICAO procedures require the decimal point be spoken as
"DECIMAL." The FAA will honor such usage by military
aircraft and all other aircraft required to use ICAO
Altitudes and Flight Levels
Up to but not including 18,000 feet MSL,
state the separate digits of the thousands plus the
hundreds if appropriate.
1. 12,000 one two
2. 12,500 one two thousand five hundred
At and above 18,000 feet MSL (FL 180),
state the words "flight level" followed by the separate
digits of the flight level.
1. 190 Flight Level
One Niner Zero
2. 275 Flight Level Two Seven Five
The three digits of bearing,
course, heading, or wind direction should always be
magnetic. The word "true" must be added when it applies.
1. (Magnetic course) 005
zero zero five
2. (True course) 050 zero five zero true
3. (Magnetic bearing) 360 three six zero
4. (Magnetic heading) 100 heading one zero
5. (Wind direction) 220 wind two two zero
The separate digits of the
speed followed by the word "KNOTS." Except, controllers may
omit the word "KNOTS" when using speed adjustment
procedures; e.g., "REDUCE/INCREASE SPEED TO TWO FIVE ZERO."
(Speed) 250 two five zero knots
(Speed) 190 one niner zero knots
The separate digits of the
Mach Number preceded by "Mach."
(Mach number) 1.5 Mach one point five
(Mach number) 0.64 Mach point six four
(Mach number) 0.7 Mach point seven
FAA uses Coordinated Universal Time (UTC)
for all operations. The word "local" or the time zone
equivalent shall be used to denote local when local time
is given during radio and telephone communications. The
term "Zulu" may be used to denote UTC.
0920 UTC zero niner two zero,
zero one two zero pacific or local,
or one twenty AM
To convert from Standard Time to
Coordinated Universal Time:
Standard Time to Coordinated
Eastern Standard Time
Central Standard Time
Mountain Standard Time
Pacific Standard Time
Alaska Standard Time
Hawaii Standard Time
Add 5 hours
Add 6 hours
Add 7 hours
Add 8 hours
Add 9 hours
Add 10 hours
For daylight time, subtract 1 hour.
A reference may be made to local daylight
or standard time utilizing the 24-hour clock system. The
hour is indicated by the first two figures and the minutes
by the last two figures.
0000 zero zero zero zero
0920 zero niner two zero
Time may be stated in minutes only (two
figures) in radiotelephone communications when no
misunderstanding is likely to occur.
Current time in use at a station is stated
in the nearest quarter minute in order that pilots may use
this information for time checks. Fractions of a quarter
minute less than 8 seconds are stated as the preceding
quarter minute; fractions of a quarter minute of 8 seconds
or more are stated as the succeeding quarter minute.
0929:05 time, zero niner two niner
0929:10 time, zero niner two niner and
Communications with Tower when Aircraft Transmitter or
Receiver or Both are Inoperative
a. Arriving Aircraft.
If you have reason to believe your
receiver is inoperative, remain outside or above the
Class D surface area until the direction and flow of
traffic has been determined; then, advise the tower of
your type aircraft, position, altitude, intention to
land, and request that you be controlled with light
AIM, Traffic Control Light Signals, Paragraph
When you are approximately 3 to 5 miles
from the airport, advise the tower of your position
and join the airport traffic pattern. From this point
on, watch the tower for light signals. Thereafter, if
a complete pattern is made, transmit your position
downwind and/or turning base leg.
inoperative. Remain outside or
above the Class D surface area until the direction and
flow of traffic has been determined; then, join the
airport traffic pattern. Monitor the primary local
control frequency as depicted on Sectional Charts for
landing or traffic information, and look for a light
signal which may be addressed to your aircraft. During
hours of daylight, acknowledge tower transmissions or
light signals by rocking your wings. At night,
acknowledge by blinking the landing or navigation
lights. To acknowledge tower transmissions during
daylight hours, hovering helicopters will turn in the
direction of the controlling facility and flash the
landing light. While in flight, helicopters should show
their acknowledgement of receiving a transmission by
making shallow banks in opposite directions. At night,
helicopters will acknowledge receipt of transmissions by
flashing either the landing or the search light.
3. Transmitter and
outside or above the Class D surface area until the
direction and flow of traffic has been determined; then,
join the airport traffic pattern and maintain visual
contact with the tower to receive light signals.
Acknowledge light signals as noted above.
b. Departing Aircraft.
If you experience radio failure
prior to leaving the parking area, make every effort to
have the equipment repaired. If you are unable to have the
malfunction repaired, call the tower by telephone and
request authorization to depart without two-way radio
communications. If tower authorization is granted, you
will be given departure information and requested to
monitor the tower frequency or watch for light signals as
appropriate. During daylight hours, acknowledge tower
transmissions or light signals by moving the ailerons or
rudder. At night, acknowledge by blinking the landing or
navigation lights. If radio malfunction occurs after
departing the parking area, watch the tower for light
signals or monitor tower frequency.
14 CFR Section 91.125 and 14 CFR Section 91.129.
Communications for VFR Flights
FSS's and Supplemental Weather Service
Locations (SWSL's) are allocated frequencies for different
functions; for example, 122.0 MHz is assigned as the En
Route Flight Advisory Service frequency at selected FSS's.
In addition, certain FSS's provide Local Airport Advisory
on 123.6 MHz. Frequencies are listed in the A/FD. If you
are in doubt as to what frequency to use, 122.2 MHz is
assigned to the majority of FSS's as a common en route
In order to expedite communications, state the frequency
being used and the aircraft location during initial callup.
Dayton radio, this is November One Two Three Four Five on
one two two point two, over Springfield V-O-R, over.
Certain VOR voice channels are being
utilized for recorded broadcasts; i.e., ATIS, HIWAS, etc.
These services and appropriate frequencies are listed in
the A/FD. On VFR flights, pilots are urged to monitor
these frequencies. When in contact with a control
facility, notify the controller if you plan to leave the
frequency to monitor these broadcasts.