NATO Phonetic Alphabet
Authority: ICAO Annex 10 to the Convention on International Civil Aviation, Volume II ยง5.2 (Radiotelephony Procedures)
The ICAO/NATO spelling alphabet assigns a code word to each letter to prevent confusion over radio: Alfa, Bravo, Charlie, Delta, Echo, Foxtrot, Golf, Hotel, India, Juliett, Kilo, Lima, Mike, November, Oscar, Papa, Quebec, Romeo, Sierra, Tango, Uniform, Victor, Whiskey, Xray, Yankee, Zulu. Note the official spellings Alfa and Juliett, not the common English "Alpha" and "Juliet."
| Letter | Code Word | Phonetic Pronunciation |
|---|---|---|
| A | Alfa | AL FAH |
| B | Bravo | BRAH VOH |
| C | Charlie | CHAR LEE |
| D | Delta | DELL TAH |
| E | Echo | ECK OH |
| F | Foxtrot | FOKS TROT |
| G | Golf | GOLF |
| H | Hotel | HOH TELL |
| I | India | IN DEE AH |
| J | Juliett | JEW LEE ETT |
| K | Kilo | KEY LOH |
| L | Lima | LEE MAH |
| M | Mike | MIKE |
| N | November | NO VEM BER |
| O | Oscar | OSS CAH |
| P | Papa | PAH PAH |
| Q | Quebec | KEH BECK |
| R | Romeo | ROW ME OH |
| S | Sierra | SEE AIR RAH |
| T | Tango | TANG GO |
| U | Uniform | YOU NEE FORM |
| V | Victor | VIK TAH |
| W | Whiskey | WISS KEY |
| X | Xray | ECKS RAY |
| Y | Yankee | YANG KEY |
| Z | Zulu | ZOO LOO |
History & Origin
The ICAO/NATO spelling alphabet in use today replaced "Able Baker," the system used by US and UK armed forces through WWII and adopted for international civil aviation in 1946 -- built around English-speaker intuition, which caused confusion once aviation and radio communication went global. Between 1948 and 1949, ICAO worked with linguist Jean-Paul Vinay to design a replacement, testing candidate words in hundreds of thousands of comprehension trials involving speakers of 31 nationalities, since a word's usefulness depends on how well it survives mixed in with the other 25, not how clear it sounds alone.
A first revision took effect April 1, 1952, but further testing turned up confusing word pairs, so ICAO revised it once more; the version used today became effective March 1, 1956 and has not changed since. Two of its spellings look like typos to English speakers but are deliberate: Alfa uses an "f" because "ph" is not reliably read as an f-sound in every language, and Juliett carries a double t because French speakers otherwise tend to treat a single final t as silent.
The Digit Words
The same radiotelephony standard assigns modified pronunciations to the ten digits for the same reason as the letters: to survive weak signal, accents, and background noise. Three is transmitted as "tree" so it isn't lost as a soft, sibilant sound; four becomes "fower" so it can't collapse into "for"; five is "fife"; and nine is spoken as "niner," partly so it can't be mistaken for the German word for "no." Zero, one, two, six, seven, and eight keep their ordinary English pronunciation.
Pilots, air traffic controllers, and ship radio operators combine the letter and digit words in the same transmissions -- reading back a callsign, a runway number, or a radio frequency -- so the same alphabet underlies far more of aviation and maritime communication than just spelling out names.