“"Before 1956, 'B' and 'D' sounded the same on a static-filled radio. That was a problem."”
The International Radiotelephony Spelling Alphabet—Alpha, Bravo, Charlie, Delta, Foxtrot, Golf, Hotel, India, Juliett, Kilo, Lima, Mike, November, Oscar, Papa, Quebec, Romeo, Sierra, Tango, Uniform, Victor, Whiskey, X-ray, Yankee, Zulu—was adopted by the International Civil Aviation Organization (ICAO) in 1956. Before that, the U.S. military used its own system (Able, Baker, Charlie, Dog, Easy, Fox, George, How, Item, Jig, King, Love, Mike, Nan, Oboe, Peter, Queen, Roger, Sugar, Tare, Uncle, Victor, William, X-ray, Yoke, Zebra) while the British used a different one (Apple, Beer, Charlie, Don, Edward, Freddie, George, Harry, Ink, Johnnie, King, London, Monkey, Nuts, Orange, Pip, Queen, Robert, Sugar, Toc, Uncle, Vic, William, X-ray, Yorker, Zebra). The confusion was legendary. A 1955 NATO conference standardized the alphabet after years of testing for clarity across languages and accents. The pronunciation was carefully chosen to be distinct even over poor radio channels. The word "Roger" for "received" survives from the old Morse code procedure signal "R" and remains in use, though "Wilco" (will comply) has replaced it in some contexts.
Standardized phraseology—including the phonetic alphabet, numerical pronunciation ("tree," "fife," "niner"), and structured communication protocols—is mandated by ICAO and the FAA to reduce miscommunication, a leading cause of aviation accidents.