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A Brief History of 5 ATC Terms

Date: January 10, 2018 Category: Blog
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Aviation terms and phraseology are used to facilitate effective communication between pilots and air traffic controllers, and many ATC terms are even used outside of the aviation industry. You may already know the language used by pilots and air traffic controllers, but do you know the history behind the most well known ATC phrases? Here’s a look at five ATC terms with origins that may surprise you.


During World War II, the Allied forces developed the transponder to identify their military aircraft on radar. The British code name for the transponder was the “Parrot”, while Americans used “Identification Friend or Foe”, or IFF. Radio operators would instruct Allied aircraft to identify themselves using the phrase “squawk your Parrot”. When they wanted pilots to turn their transponders off, they would say, “strangle your Parrot.” Today, squawk codes are used to identify aircraft and assist air traffic controllers in separating traffic.


This radio distress call is said to have originated in 1923 by Frederick Stanley Mockford, a senior radio officer in London. When asked to come up with a word to indicate an emergency that could be understood by all pilots and ground staff, he suggested “mayday,” from the French expression “m’aider” (‘help me’). Today, mayday is used as an international radio distress call and means that the lives on board are in danger and require crucial assistance.

Pan Pan

“Pan Pan” is a slightly less urgent radio distress call than Mayday. The phrase comes from the French word “panne” which means “broken down”. The call should be repeated three times to indicate a state of urgency.


NOTAM, an acronym for Notice to Airmen, is a warning issued by government agencies and airport operators to alert pilots of potential safety hazards along their flight route. The term came into use in 1947 after the International Civil Aviation Organization (ICAO) was established. New automated digital systems make it easier to search for NOTAMs, which should be checked before every flight.


In the original RAF phonetic alphabet, “Roger” was voice code for the letter “R” (today, it’s Romeo). Pilots use the phrase “Roger” to stand for “received” indicating that a radio transmission has been received. It should be noted that “Roger” simply means that someone has heard what was said, and does not connote permissions or authorizations from ATC.

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