No superfluous syllables
Abbreviations like these are common in every facet of aviation, where the highest possible level of precision and unambiguity in the language used is absolutely essential. That is especially true for the communications between the cockpit and air traffic control, or ATC for short. Any superfluous syllable, number or series of letters could lead to potential misunderstandings. So the command “reduce to minimum” doesn’t apply just to altitude and speed when an aircraft is on approach, but to the whole way aviation phraseology is developed.
Aviation language is based on the alphabet of the International Civil Aviation Organization – the ICAO alphabet. While it’s easy to mix up the letters “M” and “N” through headphones when there is crackling and interference in the background, confusing “Mike” and “November” far less likely. In pilot lingo, flight “BA 284” from San Francisco to London becomes “Bravo Alpha Two Eight Four”.
If this flight is to keep its slot for takeoff based on the calculated takeoff time (CTOT in aviation-speak), the pilot must request clearance to taxi from the ATC tower in good time. Toward runway 28R, for example. The answer from the tower might be as follows: “Bravo Alpha Two Eight Four heavy taxi to runway 28R via Alpha, Quebec, Bravo, Foxtrot, hold short of 01Lima”.
“Heavy” refers to the Boeing 787-9 Dreamliner, the aircraft operating the flight, indicating a takeoff weight of more than 300,000 pounds. Alpha, Quebec, Bravo and Foxtrot signal the way across the apron. Next comes the instruction to wait up ahead of runway 01L, which crosses runway 28R. It is in that direction that BA 284 will taxi to next.
What sounds like secret code is really only pared-down command language: “rotate”, “positive climb”, “gear up”. The weather might be described as CAVOK: “clouds and visibility OK”.
In addition to normal radio communication systems, commercial aircraft are equipped with transponders – a portmanteau of the words “transmitter” and “responder”. The main use of these telecommunications devices is to identify aircraft. But they are also deployed for emergency communications if the radio is down or a radio message isn’t appropriate in the given situation.
If the aircraft is being hijacked, for example, the code “7500” is entered. To help them remember this, trainee pilots learn the rhyme “75 – taken alive.” The code for radio failure is “7600”, while “7700” means there is an emergency. Assigned to the respective flight number, the code then appears on the screens of all air traffic controllers who are currently monitoring that flight’s airspace.