Aviation Radio Communication: How Pilots Talk to ATC

Why radio phraseology exists

The FAA's Aeronautical Information Manual (AIM) says radio communications are a critical link in the air traffic control system. It can be a strong bond between pilot and controller, or it can break with surprising speed and with disastrous results. The AIM says the single most important thought in pilot-controller communications is understanding.

It asks for brevity, because contacts should be kept short, but also for completeness, because controllers have to know what you want to do. When standard phrases don't cover it, the AIM says to use whatever words are needed to get the message across.

The first call: who, who, where, what

The AIM calls your first call to a facility the initial contact. It follows a set order:

1. The name of the facility you're calling.
2. Your full aircraft identification.
3. Your position, if you're on an airport surface.
4. The type of message, or your request if it is short.
5. The word "Over" if it is needed.

The AIM's examples show the shape: "Miami Center, Baron Five Six Three Hotel, request V-F-R traffic advisories." On the ground it might be "Columbia Ground, Cessna Three One Six Zero Foxtrot, south ramp, I-F-R Memphis."

If you expect the radio to work first time, the AIM says adding your request, your position or altitude, and the phrase "Information Charlie received" (when you have the airport weather broadcast) helps cut down frequency congestion. It also warns not to overload the controller with unneeded information.

Call signs

Civil pilots usually say the aircraft type, model or maker's name followed by the registration, and drop the N. A Bonanza with registration N655G becomes "Bonanza Six Five Five Golf". The numbers and letters use the phonetic alphabet.

The AIM says you should not abbreviate a call sign on first contact, or whenever other aircraft nearby have similar numbers or letters. Once contact is established, controllers may shorten the call sign of some aircraft to the type prefix plus the last three digits or letters, and the pilot may use the short form in later calls. If there is doubt about who a clearance was meant for, the AIM suggests the phrase "Verify clearance for" followed by your complete call sign.

Standard acknowledgements

The AIM tells pilots to acknowledge each ATC communication with their aircraft identification and one of the words "Wilco," "Roger," "Affirmative," "Negative," or another appropriate remark. Its example is "Piper Two One Four Lima, Roger."

In the FAA's Pilot/Controller Glossary, Roger means you have received all of the last transmission, and it is not an answer to a question that needs yes or no. Wilco means you have received the message, understand it and will comply.

Radio technique: the habits that matter

• Listen before you transmit. If you hear someone talking, keying up will probably block their receivers and make them repeat the call. After changing frequency, pause and make sure it's clear.
• Think before you key. Know what you want to say, and write down anything long, such as a flight plan or an IFR position report.
• Speak normally. The AIM says to hold the microphone close to your lips, pause slightly after pressing the button so the first word isn't cut off, and use a normal conversational tone.
• Wait a few seconds before calling again. The controller may be writing, looking for your flight plan or switching transmitters.
• Check for a stuck mike. If the frequency goes quiet or blocked, check your volume, your frequency and whether your microphone is stuck in transmit.

Range: VHF is line of sight

The AIM reminds pilots that higher altitude increases the range of VHF line-of-sight communications, and that remote radio sites don't always transmit and receive on all of a facility's frequencies. You may hear a station you can't reach.

Keep it professional

The AIM is direct about tone: good phraseology enhances safety and is the mark of a professional pilot, and jargon, chatter and "CB" slang have no place in ATC communications. It also recommends studying the Pilot/Controller Glossary, the same glossary used by controllers.

How to practice

• Write out your calls before each flight, then say them aloud in the car.
• Listen to your local tower and approach frequencies to hear the rhythm of real traffic.
• Ask your instructor to role-play controller calls during ground sessions.

Final thoughts

Good radio work is mostly preparation: know who you're calling, say who you are, state where you are and what you want, and be brief. The AIM is free online and worth reading in full. Chapter 4, section 2 covers everything on this page.

Frequently Asked Questions

What is the format for a pilot's first call to ATC?

The AIM's order is the name of the facility, your full aircraft identification, your position if you're on an airport surface, then your request or type of message, and the word Over if needed.

Can pilots shorten their call sign?

Not on first contact, and not when nearby aircraft have similar call signs. After contact is established, controllers may use the type prefix and the last three digits or letters of some civil aircraft, and the pilot may then use that short form.

What does Wilco mean?

In the FAA's Pilot/Controller Glossary, Wilco means you have received the message, understand it and will comply with it.

What is a stuck mike?

It's an unintentional, continuous transmission that blocks a frequency. The AIM tells pilots to check their volume, frequency and microphone if they hear nothing or the frequency seems blocked.