LAPD phonetic alphabet

The LAPD radio alphabet is a spelling alphabet, similar to the ICAO radiotelephony alphabet, that is used by the Los Angeles Police Department (LAPD) and other local and state law enforcement agencies across the state of California and elsewhere in the United States. It is the "over the air" communication used for properly understanding a broadcast of letters in the form of easily understood words. Despite often being called a "phonetic alphabet", it is not a in for transcribing phonetics.

At some point in the early history of emergency service mobile radio systems, the LAPD developed its own radio spelling alphabet for relaying precise information on individual letters. For example, the license plate "8QXG518" might be read by a civilian as "eight cue ex gee five eighteen" but with accuracy being paramount, the police dispatcher would say "eight queen x-ray george five one eight." Despite the development in 1941 of the Joint Army/Navy Phonetic Alphabet and its replacement, circa 1956, by the NATO phonetic alphabet (currently used by all NATO armed forces, civil aviation, telecommunications, and some law enforcement agencies), the LAPD and other law enforcement and emergency service agencies throughout the United States continue to use their traditional system.

The origin of the name Adam-12 from the television series with that same title is believed to have come from this alphabet. To the present, the LAPD calls its basic two-man patrol car an “A” unit – and the letter “A” is spoken as “Adam” in the phonetic alphabet. So 1-Adam-12 translates to [Division] One (LAPD Central Division) Two Man Patrol Car (Adam unit) in patrol car 12. The 12 refers to what is called "The Basic Car Plan". That is the patrol area within the Division (precinct). Specialized units use the last numbers as designating the officers. An example would be 6U2, Hollywood Division report writing unit is an example. The patrol car, in LAPD jargon, is called a Black and White owing to the colors. The number that is on the car is called the shop number and is only used for identifying the vehicle.

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