Radio phraseology is a shared, compact language. It exists so that a crowded frequency still works and nothing important is misheard.
The shape of a call
Most calls follow the same pattern: who you are calling, who you are, where you are, what you want.
Riyadh Ground, SVA123, stand 25, information Bravo, request taxi.
Keep it short, think before you press the button, and do not step on another station: listen for a gap first.
Letters and numbers
Letters use the ICAO alphabet: Alfa, Bravo, Charlie, Delta, Echo, Foxtrot, Golf, Hotel, India, Juliett, Kilo, Lima, Mike, November, Oscar, Papa, Quebec, Romeo, Sierra, Tango, Uniform, Victor, Whiskey, X-ray, Yankee, Zulu. Practise them with the phonetic trainer.
Numbers are spoken digit by digit, with a few traditional pronunciations: tree (3), fife (5) and niner (9).
| What | Written | Spoken |
|---|---|---|
| Flight level | FL350 | flight level three five zero |
| Altitude | 4,000 ft | four thousand feet |
| Altitude | 12,500 ft | one two thousand five hundred feet |
| Heading | 270° | heading two seven zero |
| Speed | 250 kt | two five zero knots |
| Frequency | 118.700 | one one eight decimal seven |
| Squawk | 4521 | squawk four five two one |
| Runway | 09L | runway zero niner left |
What you must read back
Read back, in full, every instruction that could cause a problem if misheard:
- Route clearances.
- Any clearance to enter, land on, take off from, hold short of, cross, taxi on or backtrack on a runway.
- Runway in use, altimeter settings, squawk codes and new frequencies.
- Level, heading and speed instructions, and transition levels.
End each readback with your callsign. Simple information, such as traffic or the weather, can be acknowledged with your callsign alone.
An IFR clearance
Clearances follow a predictable order. Many pilots remember it as CRAFT: Clearance limit, Route, Altitude, Frequency, Transponder.
ATC: SVA123, cleared to London Heathrow, DEMAP 1E departure, climb flight level one two zero, squawk two three four one.
You: Cleared to London Heathrow, DEMAP 1E departure, climb flight level one two zero, squawk two three four one, SVA123.
Useful words
| Word | Meaning |
|---|---|
| Affirm | Yes |
| Negative | No |
| Roger | I have received all of your last transmission (not a yes) |
| Wilco | I understand and will comply |
| Standby | Wait, I will call you back |
| Unable | I cannot comply |
| Say again | Repeat your last transmission |
| Correction | I made an error; the correct version is… |
For flight simulation and training only. Real-world procedures vary by country and operator; always follow the published charts and your local rules.
Keep reading
- How air traffic control works: The controller positions you meet on a flight, what each one does, and when you change frequency.
- Squawk codes and emergencies: The transponder codes everyone should know, how to declare an emergency, and what to do if the radio fails.