Voice procedure
Encyclopedia
Voice procedure includes various techniques used to clarify, simplify and standardize spoken communications over two-way radio
s, in use by the military, in civil aviation
, police and fire dispatching systems, citizens' band radio
(CB), etc.
Voice procedure communications are intended to maximize clarity of spoken communication and reduce misunderstanding. It consists of signalling protocol such as the use of abbreviated codes like the CB radio ten-code
, Q code
s in amateur radio
and aviation, police codes, etc., and jargon.
Some elements of voice procedure are understood across many applications, but significant variations exist. The military of the NATO countries have similar procedures in order to make cooperation easier, and pseudo-military organizations often base their procedures on them, so some commonality exists there.
.
"Roger" was the U.S. military designation for the letter R (as in received) from 1927 to 1957.
uses the term phraseology
to describe voice procedure or communications protocols used over telecommunications circuits. An example is air traffic control radio communications. Standardized wording is used and the person receiving the message may repeat critical parts of the message back to the sender. This is especially true of safety-critical messages. Consider this example of an exchange between a controller and an aircraft:
Aircraft: Boston Tower, Warrior tree (three) fife foxtrot, holding short of two two right.
Tower: Warrior Tree fife foxtrot, Boston Tower, runway two two right, cleared for immediate takeoff.
Aircraft: Roger, tree fife foxtrot, cleared for immediate takeoff, two two right.
On telecommunications circuits, disambiguation is a critical function of voice procedure. Due to any number of variables, including radio static, a busy or loud environment, or similarity in the phonetics of different words, a critical piece of information can be misheard or misunderstood; for instance, a pilot being ordered to eleven thousand as opposed to seven thousand. To reduce ambiguity, critical information may be broken down and read as separate letters and numbers. To avoid error or misunderstanding, pilots will often read back altitudes in the tens of thousands using both separate numbers and the single word (example: given a climb to 10,000 ft, the pilot replies "[Callsign] climbing to One zero, Ten Thousand"). However, this is usually only used to differentiate between 10,000 and 11,000 ft since these are the most common altitude deviations. The runway number read visually as eighteen, when read over a voice circuit as part of an instruction, becomes one eight. In some cases a spelling alphabet
is used (also called a radio alphabet or a phonetic alphabet) . Instead of the letters AB, the words Alpha Bravo are used. Main Street becomes Mike Alpha India November street, clearly separating it from Drain Street and Wayne Street. The numbers 5 and 9 are pronounced "fife" and "niner" respectively, since "five" and "nine" can sound the same over the radio.
Over fire service radios, phraseology may include words that indicate the priority of a message, for example:
or
Words may be repeated to modify them from traditional use in order to describe a critical message:
Police Radios also use this technique to escalate a call that is quickly becoming an emergency.
Railroads have similar processes. When instructions are read to a locomotive engineer
, they are preceded by the engineer's name, direction of travel, and the train or locomotive
number. This reduces the possibility that a set of instructions will be acted on by the wrong locomotive engineer:
Phraseology on telecommunications circuits may employ special phrases like ten codes
, Sigalert, Quick Alert! or road service towing abbreviations such as T6. This jargon may abbreviate critical data and alert listeners by identifying the priority of a message. It may also reduce errors caused by ambiguities involving rhyming
, or similar-sounding, words.
Albacore: Bronwyn, Bronwyn, Bronwyn this is Albacore, over.
Bronwyn: Albacore, this is Bronwyn, over.
Albacore: This is Albacore. Want a tow and are you ok for tea at Osbourne Bay? over.
Bronwyn: This is Bronwyn. Negative, got engine running, 1600 at clubhouse fine with us. over
Albacore: This is Albacore, Roger, out.
"Copy that" is incorrect. COPY is used when a message has been intercepted by another station, i.e. a third station would respond:
Nonesuch Brownwyn, this is Nonesuch. Copied your previous, will also see you there, out.
You should always use your own callsign when transmitting.
This system works better when the message rate and signal quality is low.
C21: Hello C33, this is C21, over.
C33: C33, [send], over.
C21: C21, have you got Sunray C10 at your location?, over.
C33: C33, Negative, I think he is with C30, over.
C21: C21, roger, out.
The advantage of this sequence is that the recipient always knows who sent the message.
The downside is that the listener only knows the intended recipient from the context of the conversation. Requires moderate signal quality for the radio operator to keep track of the conversations.
However a broadcast message and response is fairly efficient.
0: Hello charlie charlie 1, this is 0. Radio check. over.
1: 1. ok. over.
2: 2. ok. over.
3: 3. difficult. over.
4: 4. ok. over.
0: 0. 3 difficult. out. (the other stations know they can be heard by 0 as 'OK')
A charlie charlie call is used as an All Station call so as to not give away to an enemy all units and call signs on the ground.
has no voice procedure, but due to the limited range of transmission it is unlikely a transmission will be heard outside of a single party. On signals open to the public with broader reception, such as citizens band, there is only enough protocol to allow operators to speak one at a time or allow emergency traffic to go through. Otherwise, there is no prioritization or rules to the communication outside of following local and federal laws regarding communication. Other stations requiring licensure such as amateur radio
bands or MARS users (which includes civilian amateur radio operators) have strict usage and transmission rules which operators are trained on (as part of their licensing process) that allows authorized users to communicate. Regulated Radio frequencies often have unlicensed users who are unaware of the protocol on a certain channel and are asked to sign off if they fail to identify a callsign as a licensed operator, or are reported by licensed operators to the licensing body for possible advisement or citation. Amateur radio frequencies also may have assigned functions which may allow or disallow certain traffic including voice, such as continuous wave (see Morse code
) transmission or data-only transmission frequencies.
Structured use is seen in voice procedure for government, military and disaster command usage. In law enforcement
and public safety
use, voice procedure follows a protocol that governs who can speak on a frequency and when. Since modern police frequencies are on a restricted bandwidth it is unlikely that an unlicensed party will interrupt communication; all operators on a frequency are assumed to be authorized to utilize a channel unless proven otherwise. Licensed radios in law enforcement often utilize trunking
, or multiple frequencies selected by a control tower at random which prevents single-channel scanners from picking up a transmission. A frequency may be dispatch controlled (or controlled net) which is controlled by one control station and any parties wishing to use the frequency must direct all calls to the control station who routes calls as needed to necessary parties. A tactical frequency (or tactical net) has no control station, and is intended to be used on an ad-hoc basis for situations, such as multiple units attempting an arrest who surround a single property. Tactical frequencies may or may not be trunked and may be susceptible to single-channel scanner reception.
Two-way radio
A two-way radio is a radio that can both transmit and receive , unlike a broadcast receiver which only receives content. The term refers to a personal radio transceiver that allows the operator to have a two-way conversation with other similar radios operating on the same radio frequency...
s, in use by the military, in civil aviation
Civil aviation
Civil aviation is one of two major categories of flying, representing all non-military aviation, both private and commercial. Most of the countries in the world are members of the International Civil Aviation Organization and work together to establish common standards and recommended practices...
, police and fire dispatching systems, citizens' band radio
Citizens' band radio
Citizens' Band radio is, in many countries, a system of short-distance radio communications between individuals on a selection of 40 channels within the 27-MHz band. Citizens' Band is distinct from the FRS, GMRS, MURS and amateur radio...
(CB), etc.
Voice procedure communications are intended to maximize clarity of spoken communication and reduce misunderstanding. It consists of signalling protocol such as the use of abbreviated codes like the CB radio ten-code
Ten-code
Ten-codes, also known as ten signals, are code words used to represent common phrases in voice communication, particularly by law enforcement and in Citizens' Band radio transmissions....
, Q code
Q code
The Q code is a standardized collection of three-letter message encodings, also known as a brevity code, all of which start with the letter "Q", initially developed for commercial radiotelegraph communication, and later adopted by other radio services, especially amateur radio...
s in amateur radio
Amateur radio
Amateur radio is the use of designated radio frequency spectrum for purposes of private recreation, non-commercial exchange of messages, wireless experimentation, self-training, and emergency communication...
and aviation, police codes, etc., and jargon.
Some elements of voice procedure are understood across many applications, but significant variations exist. The military of the NATO countries have similar procedures in order to make cooperation easier, and pseudo-military organizations often base their procedures on them, so some commonality exists there.
Words in voice procedure
Some words with specialized meanings are used in radio communication throughout the English-speaking world, and in international radio communication, where English is the lingua francaLingua franca
A lingua franca is a language systematically used to make communication possible between people not sharing a mother tongue, in particular when it is a third language, distinct from both mother tongues.-Characteristics:"Lingua franca" is a functionally defined term, independent of the linguistic...
.
- Affirm — Yes
- Negative — No
- Reading you Five / Loud and clear — I understand what you say 5x5Five by fiveFive by five is the best of 25 possible subjective responses used to describe the quality of communications, specifically the signal-to-noise ratio. As receiving stations move away from an analog radio transmitting site, the signal strength decreases gradually while noise levels increase...
. - Over — I have finished talking and I am listening for your reply. Short for "Over to you."
- Out — I have finished talking to you and do not expect a reply.
- Roger — I understand what you just said.
- Copy — I heard what you just said.
- Wilco — Will comply (after receiving new directions).
- Go ahead or Send your traffic — Send your transmission.
- Say again — Please repeat your last message (Repeat is only used in US military radio terminology to request additional artillery fire)
- Break — Signals a pause during a long transmission to open the channel for other transmissions, especially for allowing any potential emergency traffic to get through.
- Break-Break — Signals to all listeners on the frequency, the message to follow is priority. Almost always reserved for emergency traffic or in NATO forces, an urgent 9 line9 LineLine 9 or 9 Line may refer to:*9 *Barcelona Metro line 9, one of the two branches of the Barcelona metro extension line 9/10*Mexico City Metro Line 9, a rapid transit line in Mexico City...
or Frag-O. - Standby or Wait one — Pause for the next transmission. This usually entails staying off the air until the operator returns after a short wait.
- Callsign-Actual — Sometimes an individual (generally a superior) may have a person monitor the network for them. Saying "actual" after their callsign asserts you wish to speak to the specific person the callsign is attached to.
- SécuritéSecuriteWhen a marine radio transmission begins with "Sécurité, sécurité, sécurité" , it means that what follows is important safety information. The most common use of this is by coast radio stations before the broadcast of navigational warnings and meteorological information.It is normal practice to...
— Maritime safety call. Repeated three times. Has priority over routine calls. - Pan-panPan-panIn radiotelephone communications, a call of three repetitions of pan-pan is used to signify that there is an urgency on board a boat, ship, aircraft or other vehicle but that, for the time being at least, there is no immediate danger to anyone's life or to the vessel itself. This is referred to as...
— Maritime/aviation urgency call. Repeated three times. Has priority over safety calls. - MaydayMayday (distress signal)Mayday is an emergency procedure word used internationally as a distress signal in voice procedure radio communications. It derives from the French venez m'aider, meaning "come help me"....
— Maritime/aviation distress call. Repeated three times and at beginning of every following transmission relating to the current distress situation. Has priority over urgency and safety calls.
"Roger" was the U.S. military designation for the letter R (as in received) from 1927 to 1957.
Example usage
The Federal Aviation AdministrationFederal Aviation Administration
The Federal Aviation Administration is the national aviation authority of the United States. An agency of the United States Department of Transportation, it has authority to regulate and oversee all aspects of civil aviation in the U.S...
uses the term phraseology
Phraseology
In linguistics, phraseology is the study of set or fixed expressions, such as idioms, phrasal verbs, and other types of multi-word lexical units , in which the component parts of the expression take on a meaning more specific than or otherwise not predictable from the sum of their meanings when...
to describe voice procedure or communications protocols used over telecommunications circuits. An example is air traffic control radio communications. Standardized wording is used and the person receiving the message may repeat critical parts of the message back to the sender. This is especially true of safety-critical messages. Consider this example of an exchange between a controller and an aircraft:
Aircraft: Boston Tower, Warrior tree (three) fife foxtrot, holding short of two two right.
Tower: Warrior Tree fife foxtrot, Boston Tower, runway two two right, cleared for immediate takeoff.
Aircraft: Roger, tree fife foxtrot, cleared for immediate takeoff, two two right.
On telecommunications circuits, disambiguation is a critical function of voice procedure. Due to any number of variables, including radio static, a busy or loud environment, or similarity in the phonetics of different words, a critical piece of information can be misheard or misunderstood; for instance, a pilot being ordered to eleven thousand as opposed to seven thousand. To reduce ambiguity, critical information may be broken down and read as separate letters and numbers. To avoid error or misunderstanding, pilots will often read back altitudes in the tens of thousands using both separate numbers and the single word (example: given a climb to 10,000 ft, the pilot replies "[Callsign] climbing to One zero, Ten Thousand"). However, this is usually only used to differentiate between 10,000 and 11,000 ft since these are the most common altitude deviations. The runway number read visually as eighteen, when read over a voice circuit as part of an instruction, becomes one eight. In some cases a spelling alphabet
Spelling alphabet
A spelling alphabet, radio alphabet, or telephone alphabet is a set of words which are used to stand for the letters of an alphabet. Each word in the spelling alphabet typically replaces the name of the letter with which it starts...
is used (also called a radio alphabet or a phonetic alphabet) . Instead of the letters AB, the words Alpha Bravo are used. Main Street becomes Mike Alpha India November street, clearly separating it from Drain Street and Wayne Street. The numbers 5 and 9 are pronounced "fife" and "niner" respectively, since "five" and "nine" can sound the same over the radio.
Over fire service radios, phraseology may include words that indicate the priority of a message, for example:
Forty Four Truck to the Bronx, Urgent!
or
San Diego, Engine Forty, Emergency traffic!
Words may be repeated to modify them from traditional use in order to describe a critical message:
Evacuate! Evacuate! Evacuate!
Police Radios also use this technique to escalate a call that is quickly becoming an emergency.
Code 3! Code 3! Code 3!
Railroads have similar processes. When instructions are read to a locomotive engineer
Track warrant
Track warrants are systematized permissions used on some railroad lines to authorize a train's use of the main line. Dispatchers issue these permissions to train crews instead of using signals. The crews receive track warrants by radio, phone, or electronic transmission from a...
, they are preceded by the engineer's name, direction of travel, and the train or locomotive
Locomotive
A locomotive is a railway vehicle that provides the motive power for a train. The word originates from the Latin loco – "from a place", ablative of locus, "place" + Medieval Latin motivus, "causing motion", and is a shortened form of the term locomotive engine, first used in the early 19th...
number. This reduces the possibility that a set of instructions will be acted on by the wrong locomotive engineer:
Five Sixty Six West, Engineer Jones, okay to proceed two blocks west to Ravendale.
Phraseology on telecommunications circuits may employ special phrases like ten codes
Ten-code
Ten-codes, also known as ten signals, are code words used to represent common phrases in voice communication, particularly by law enforcement and in Citizens' Band radio transmissions....
, Sigalert, Quick Alert! or road service towing abbreviations such as T6. This jargon may abbreviate critical data and alert listeners by identifying the priority of a message. It may also reduce errors caused by ambiguities involving rhyming
Rhyme
A rhyme is a repetition of similar sounds in two or more words and is most often used in poetry and songs. The word "rhyme" may also refer to a short poem, such as a rhyming couplet or other brief rhyming poem such as nursery rhymes.-Etymology:...
, or similar-sounding, words.
Maritime procedure
Boat "Albacore" talking to Boat "Bronwyn"Albacore: Bronwyn, Bronwyn, Bronwyn this is Albacore, over.
Bronwyn: Albacore, this is Bronwyn, over.
Albacore: This is Albacore. Want a tow and are you ok for tea at Osbourne Bay? over.
Bronwyn: This is Bronwyn. Negative, got engine running, 1600 at clubhouse fine with us. over
Albacore: This is Albacore, Roger, out.
"Copy that" is incorrect. COPY is used when a message has been intercepted by another station, i.e. a third station would respond:
Nonesuch Brownwyn, this is Nonesuch. Copied your previous, will also see you there, out.
You should always use your own callsign when transmitting.
This system works better when the message rate and signal quality is low.
British Army
Station C21(charlie-two-one) talking to C33(charlie-three-three):C21: Hello C33, this is C21, over.
C33: C33, [send], over.
C21: C21, have you got Sunray C10 at your location?, over.
C33: C33, Negative, I think he is with C30, over.
C21: C21, roger, out.
The advantage of this sequence is that the recipient always knows who sent the message.
The downside is that the listener only knows the intended recipient from the context of the conversation. Requires moderate signal quality for the radio operator to keep track of the conversations.
However a broadcast message and response is fairly efficient.
0: Hello charlie charlie 1, this is 0. Radio check. over.
1: 1. ok. over.
2: 2. ok. over.
3: 3. difficult. over.
4: 4. ok. over.
0: 0. 3 difficult. out. (the other stations know they can be heard by 0 as 'OK')
A charlie charlie call is used as an All Station call so as to not give away to an enemy all units and call signs on the ground.
Frequency control
In public radio, voice procedure controls the behavior and use of the frequency between each operator. Deregulated frequencies, such as Family Radio ServiceFamily Radio Service
The Family Radio Service is an improved walkie talkie radio system authorized in the United States since 1996. This personal radio service uses channelized frequencies in the ultra high frequency band. It does not suffer the interference effects found on citizens' band at 27 MHz, or the...
has no voice procedure, but due to the limited range of transmission it is unlikely a transmission will be heard outside of a single party. On signals open to the public with broader reception, such as citizens band, there is only enough protocol to allow operators to speak one at a time or allow emergency traffic to go through. Otherwise, there is no prioritization or rules to the communication outside of following local and federal laws regarding communication. Other stations requiring licensure such as amateur radio
Amateur radio
Amateur radio is the use of designated radio frequency spectrum for purposes of private recreation, non-commercial exchange of messages, wireless experimentation, self-training, and emergency communication...
bands or MARS users (which includes civilian amateur radio operators) have strict usage and transmission rules which operators are trained on (as part of their licensing process) that allows authorized users to communicate. Regulated Radio frequencies often have unlicensed users who are unaware of the protocol on a certain channel and are asked to sign off if they fail to identify a callsign as a licensed operator, or are reported by licensed operators to the licensing body for possible advisement or citation. Amateur radio frequencies also may have assigned functions which may allow or disallow certain traffic including voice, such as continuous wave (see Morse code
Morse code
Morse code is a method of transmitting textual information as a series of on-off tones, lights, or clicks that can be directly understood by a skilled listener or observer without special equipment...
) transmission or data-only transmission frequencies.
Structured use is seen in voice procedure for government, military and disaster command usage. In law enforcement
Law enforcement agency
In North American English, a law enforcement agency is a government agency responsible for the enforcement of the laws.Outside North America, such organizations are called police services. In North America, some of these services are called police while others have other names In North American...
and public safety
Public Safety
Public safety involves the prevention of and protection from events that could endanger the safety of the general public from significant danger, injury/harm, or damage, such as crimes or disasters .-See also:* By nation...
use, voice procedure follows a protocol that governs who can speak on a frequency and when. Since modern police frequencies are on a restricted bandwidth it is unlikely that an unlicensed party will interrupt communication; all operators on a frequency are assumed to be authorized to utilize a channel unless proven otherwise. Licensed radios in law enforcement often utilize trunking
Trunking
In modern communications, trunking is a concept by which a communications system can provide network access to many clients by sharing a set of lines or frequencies instead of providing them individually. This is analogous to the structure of a tree with one trunk and many branches. Examples of...
, or multiple frequencies selected by a control tower at random which prevents single-channel scanners from picking up a transmission. A frequency may be dispatch controlled (or controlled net) which is controlled by one control station and any parties wishing to use the frequency must direct all calls to the control station who routes calls as needed to necessary parties. A tactical frequency (or tactical net) has no control station, and is intended to be used on an ad-hoc basis for situations, such as multiple units attempting an arrest who surround a single property. Tactical frequencies may or may not be trunked and may be susceptible to single-channel scanner reception.
See also
- Five by fiveFive by fiveFive by five is the best of 25 possible subjective responses used to describe the quality of communications, specifically the signal-to-noise ratio. As receiving stations move away from an analog radio transmitting site, the signal strength decreases gradually while noise levels increase...
- ICAO spelling alphabet
- List of international common standards
- MaydayMayday (distress signal)Mayday is an emergency procedure word used internationally as a distress signal in voice procedure radio communications. It derives from the French venez m'aider, meaning "come help me"....
- Procedure wordProcedure wordProcedure words or prowords are words or phrases limited to radio telephone procedure used to facilitate communication by conveying information in a condensed standard form. - OUT :...
- Station identificationStation identificationStation identification is the practice of radio or television stations or networks identifying themselves on air, typically by means of a call sign or brand name...