+ Letter names Alfa November Bravo Oscar Charlie Papa Delta Quebec Echo Romeo Foxtrot Sierra Golf Tango Hotel Uniform India Victor Juliett Whiskey Kilo Xray Lima Yankee Mike Zulu One Six Two Seven Three ('tree') Eight Four ('fower') Nine ('niner') Five ('fife') Zero The NATO phonetic alphabet, officially the International Radiotelephony Spelling Alphabet, is an internationally recognized set of names for the letters of the Latin alphabet and the Arabic digits. It is most commonly used in radio communication, where the usual names of the letters are likely to be misheard. It was defined in 1955–1956 by the International Civil Aviation Organization (ICAO).
Usage "Spelling alphabets" are used to distinguish letters when spelling out words. The alphabet is designed to minimize potential confusion, as radio and telephonic communication can be subject to static or other interference. For example, the message "proceed to map grid DH98" would be read out as "proceed to map grid Delta-Hotel-Niner-Eight".
Although such codes are commonly called "phonetic alphabets", they are not phonetic in the sense of phonetic transcription systems such as the International Phonetic Alphabet, nor are they alphabets used to write out messages, but rather clearer names for the letters of an alphabet.
Civilian industry uses the code words to avoid similar problems in the transmission of messages by telephone systems. For example, it is often used in the retail industry, where customer or site details are conveyed by telephone (e.g., to authorize a credit agreement or confirm stock codes), though ad hoc code words are often used in that instance. It has been used by information technology workers to communicate, by voice, very long serial numbers and reference codes. Most major airlines use the alphabet to communicate passenger name records (PNRs) internally, and in some cases, with customers. It is often used in a medical context as well.
The 26 code words are as follows (ICAO spellings): , Bravo, Charlie, Delta, Echo, Foxtrot, Golf, Hotel, India, , Kilo, Lima, Mike, November, Oscar, Papa, Quebec, Romeo, Sierra, Tango, Uniform, Victor, Whiskey, Xray, Yankee, and Zulu.In print, these code words are commonly capitalized or written in all caps for visual salience (CCEB 2016). and are spelled that way to avoid mispronunciation by people unfamiliar with English orthography; NATO changed to for the same reason. The code words for digits are their English names, though with their pronunciations modified in the cases of three, four, five, nine, and thousand.
Several codes words and sequences of code words have become well-known, such as Bravo Zulu (letter code BZ) for "well done", Checkpoint Charlie (Checkpoint C) in Berlin, and Zulu Time for Greenwich Mean Time or Coordinated Universal Time. During the Vietnam War, the US government referred to the Viet Cong guerrillas and the group itself as VC, or Victor Charlie; the name "Charlie" became synonymous with this force.
Pronunciation of code words Design
To create the code, a series of international agencies assigned 26 clear-code words (also known as "phonetic words") acrophonically to the letters of the Latin alphabet, with the goal that the letters and numbers would be easily distinguishable from one another over radio and telephone. The words were chosen to be accessible to speakers of English, French and Spanish. Some of the code words were changed over time, as they were found to be ineffective in real-life conditions.
The final choice of code words for the letters of the alphabet and for the digits was made after hundreds of thousands of comprehension tests involving 31 nationalities. The qualifying feature was the likelihood of a code word being understood in the context of others. For example, Football has a higher chance of being understood than Foxtrot in isolation, but Foxtrot is more often understood when combined with other words in the spelling alphabet.
Pronunciations were set out by the ICAO before 1956 with advice from the governments of both the United States and United Kingdom.L.J. Rose, "Aviation's ABC: The development of the ICAO spelling alphabet", ICAO Bulletin 11/2 (1956) 12–14. To eliminate national variations in pronunciation, posters illustrating the pronunciation desired by ICAO are available. However, there remain differences in the pronunciations published by ICAO and other agencies, and ICAO has apparently conflicting Latin-alphabet and IPA transcriptions. At least some of these differences appear to be typographic errors. In 2022, the Deutsches Institut für Normung (DIN) attempted to resolve these conflicts. For example, they consistently transcribe for what the ICAO had transcribed variously as in IPA and as a, ah, ar, er in orthography.
In the official version of the alphabet, two spellings deviate from the English norm: Alfa and Juliett. Alfa is spelled with an f as it is in most European languages because the spelling Alpha may not be pronounced properly by native speakers of some languages – who may not know that ph should be pronounced as f. The spelling Juliett is used rather than Juliet for the benefit of French speakers, because they may otherwise treat a single final t as silent. For similar reasons, Charlie and Uniform have recognized alternative pronunciations where the ch is pronounced "sh" and the u is pronounced "oo", though these are not present on the NATO chart. Early on, the NATO alliance changed X-ray to Xray in its version of the alphabet to ensure that it would be pronounced as one word rather than as two,Albert Pelsser, La storia postale dell' ICAO , translated by Nico Michelini while the global organization ICAO keeps the spelling X-ray.
Numerical digits Just as words are spelled out as individual letters, numbers are spelled out as individual digits. That is, 17 is rendered as one seven and 60 as six zero. Depending on context, the word thousand may be used as in English, and, for whole hundreds only (when the sequence 00 occurs at the end of a number), the word hundred may be used. For example, 1300 is read as one three zero zero if it is a transponder code or serial number, and as one thousand three hundred if it is an altitude or distance.
The ICAO, NATO, and FAA use modifications of English digits as code words, with 3, 4, 5 and 9 being pronounced tree, fower (rhymes with lower), fife and niner. The digit 3 is specified as tree so that it will not be mispronounced sri (and similarly thousand is pronounced tousand); the long pronunciation of 4 (still found in some English dialects) keeps it somewhat distinct from for; 5 is pronounced with a second "f" because the normal pronunciation with a "v" is easily confused with "fire"; and 9 has an extra syllable to keep it distinct from the German word nein "no".Camelia Uşurelu (2019: 461) Studii lingvistice. In memoriam Cristina Călăraşu. Editura Universităţii din Bucureşti (Prior to 1956, three and five had been pronounced with the English consonants, but with the vowels broken into two syllables.) For directions presented as the hour-hand position on a clock, the additional numerals "ten", "eleven" and "twelve" are used with the word "o'clock".
The ITU and IMO, however, specify a different set of code words for digits. During 1947, the ITU adopted the compound Latinate prefix-number words (Nadazero, Unaone, etc.), later adopted by the IMO during 1965. Nadazero – from Spanish or Portuguese nada + NATO/ICAO zero Unaone – generic Romance una, from Latin ūna + NATO/ICAO one Bissotwo – from Latin bis + NATO/ICAO two. (1959 ITU proposals bis and too) Terrathree – from Italian terzo + NATO/ICAO three ("tree") (1959 ITU proposals ter and tree) Kartefour – from French quatre (Latin quartus) + NATO/ICAO four ("fow-er") (1959 ITU proposals quarto and fow-er) Pantafive – from Greek penta- + NATO/ICAO five ("fife") (from 1959 ITU proposals penta and fife) Soxisix – from French soix + NATO/ICAO six (1959 ITU proposals were saxo and six) Setteseven – from Italian sette + NATO/ICAO seven (1959 ITU proposals sette and sev-en) Oktoeight – generic Romance octo-, from Latin octō + NATO/ICAO eight (1959 ITU proposals octo and ait) Novenine – from Italian nove + NATO/ICAO nine ("niner") (1959 ITU proposals were nona and niner) The IMO's GMDSS procedures permits the use of either set of code words.
Variants Since "Nectar" was changed to "November" in 1956, the code has been mostly stable. However, there is occasional regional substitution of a few code words, such as replacing them with earlier variants, to avoid confusion with local terminology. As of 2013, it was reported that "Delta" was often replaced by "David" or "Dixie" at Atlanta International Airport, where Delta Air Lines is based, because "Delta" is also the airline's callsign. Air traffic control once referred to Taxiway D at the same airport as "Taxiway Dixie", though this practice was officially discontinued in 2020. "Foxtrot" may be shortened to "Fox" at airports in the United States.BBC (2014) The NATO phonetic alphabet British police use "Indigo" rather than "India". In Indonesia, "London" is used in place of "Lima", because lima is the Malay word for 'five'. It has been reported that "Hawk" is sometimes used for "Hotel" in the Philippines.
Tables There are two IPA transcriptions of the letter names, from the International Civil Aviation Organization (ICAO) and the Deutsches Institut für Normung (DIN). Both authorities indicate that a non-rhotic pronunciation is standard.This is reinforced by the IMO, which for example has "TCHAH-LI" as the French respelling of Charlie and "OSS-CAH", "VIK-TAH" as the English respellings of Oscar and Victor. That of the ICAO, first published in 1950 and reprinted many times without correction (e.g. the error in 'golf'), uses a large number of vowels. For instance, it has six low/central vowels: , , , , and . The DIN consolidates all six into the single low-central vowel . The DIN vowels are partly predictable, with the more open vowels in closed syllables and the more close vowels in open syllables, apart from echo and sierra, which have as in English, German and Italian. The DIN also reduced the number of stressed syllables in bravo and x-ray, consistent with the ICAO English respellings of those words and with the NATO change of spelling of x-ray to xray so that people would know to pronounce it as a single word.
Letter code words with pronunciation Symbol Code word DIN 5009(2022) (1950) English respellingCapital letters, if any, indicate a stressed syllable. A Alfa AL fah B Bravo BRAH voh C Charlie (or ) (or ) CHAR lee (or SHAR lee)As of approximately 2018, NATO no longer indicates the alternative pronunciations of Charlie and Uniform, at least on the English-language chart; a French-language chart is apparently not available. DDelta DELL tah EEcho ECK oh FFoxtrot FOKS trot GGolf golf HHotel ho TELL IIndia IN dee ah J Juliett JEW lee ETT KKilo KEY loh LLima LEE mah MMike mike NNovember no VEM ber OOscar OSS cah PPapa pah PAH QQuebec keh BECK RRomeo ROW me oh S Sierra see AIR rah TTango TANG go UUniform (or ) (or ) (or ) VVictor VIK tah WWhiskey WISS key XXray, x-ray ECKS ray YYankee YANG key ZZulu ZOO loo
There is no authoritative IPA transcription of the digits. However, there are respellings into both English and French, which can be compared to clarify some of the ambiguities and inconsistencies.