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This page is your complete reference for communicating with ATC on VATSIM. Every call, every readback, and every phase of flight is covered here with realistic examples. Use standard ICAO phraseology and you will sound professional from your very first flight.
ATC controllers on VATSIM are volunteers who do this because they enjoy it. If you make a mistake on the radio, simply say “Correction” and try again. Controllers will help you through it - everyone was new once. Do not let fear of making a mistake stop you from flying online.

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Flight Phase Phraseology

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Requesting Your IFR Clearance

Before you push back from the gate, you need your IFR clearance from Delivery (or whichever controller is providing that service under top-down coverage). This tells you exactly how you are authorized to fly to your destination.

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When to Contact Delivery

  • After you have listened to the ATIS and noted the information letter
  • After you have programmed your FMS and are ready to copy your clearance
  • Before requesting pushback or taxi

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The CRAFT Mnemonic

ATC will issue your clearance following the CRAFT format. Have a pen ready (or a notepad app) and write down each element:
LetterElementExample
CClearance limit”Cleared to Montreal” (your destination)
RRoute”Via the DEDKI3 departure, AVSEP transition, flight planned route”
AAltitude”Climb via SID, expect flight level 350 ten minutes after departure”
FFrequency”Contact Ground 121.9 when ready to push”
TTransponder (Squawk)“Squawk 4521”

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Full Clearance Exchange

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What You Must Read Back

  • Clearance limit (destination)
  • Full route including SID and transitions
  • Altitude instructions (initial and expected)
  • Squawk code
Write down the clearance before reading it back. It is completely acceptable to say “Say again” if you missed part of the clearance. You can also ask “Say again the route” to get just one element repeated. Take your time - accuracy matters more than speed.

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If You Get a Reroute

Sometimes ATC will change your filed route. If the new clearance is significantly different from what you filed, you may need a moment to reprogram your FMS.

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Common Mistakes at This Phase

  • Not listening to ATIS before calling Delivery
  • Forgetting to include the ATIS letter in your initial call
  • Reading back only part of the clearance (you must read back the full clearance)
  • Not writing it down and then fumbling the readback

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Readback Requirements

Certain items must always be read back to ATC. If you fail to read back a required item, ATC will ask you to confirm. Here is the complete list:
ItemExample Readback
Runway assignments”Runway 05”
Altimeter settings”Altimeter 29.92”
Altitude / flight level”Flight level 350” or “Descend and maintain 4,000”
Heading assignments”Heading 210”
Speed assignments”Speed 250 knots”
Frequency changes”Contact Departure 126.4”
Squawk codes”Squawk 4521”
Hold short instructions”Hold short runway 06L”
Route clearancesFull clearance readback
Approach clearances”Cleared ILS runway 24R approach”
When in doubt, read it back. ATC will never be annoyed by a pilot confirming an instruction. It is far better to read back too much than too little.

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Essential Words and Phrases

These standard aviation terms have specific meanings. Use them correctly and your communication will be clear and professional.
Word / PhraseMeaning
Roger”I have received and understood your message.” Does NOT mean “yes.”
Wilco”I will comply with your instruction.” Only use when no readback is required.
Affirm”Yes.” Use this instead of “yes” on the radio.
Negative”No.” Use this instead of “no” on the radio.
Say again”Please repeat your last message.”
Correction”I made an error. The correct information is…”
Unable”I cannot comply with that instruction.” Always state the reason if possible.
Standby”Wait, I will get back to you.”
Go ahead”Proceed with your message.” Used when ATC is ready to hear your request.
Read back correctATC confirming that your readback was accurate.
How do you read”How is my signal quality?” Answered on a scale of 1 (unreadable) to 5 (perfectly clear).
MaydayEmergency distress call. Only use in genuine emergencies (with ATC permission on VATSIM).
Pan-PanUrgency call, less severe than Mayday.

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Common Mistakes

“Roger” means “I received your message.” “Wilco” means “I will comply.” Using both together is redundant - pick one. In most cases, a proper readback is better than either.
If ATC gives you an altitude, heading, frequency, squawk code, or hold short instruction, you must read back the specific information. Saying “Roger” alone is not sufficient. For example, if ATC says “descend flight level 240,” your response should be “descend flight level 240, Air Canada 456” - not just “Roger.”
Do not start your transmission with “Uhhhh” or a long pause. Think about what you want to say before pressing PTT. Press the button, pause for half a second, then speak clearly and concisely.
Every pilot transmission should end with your callsign. This confirms to ATC who is speaking, especially when multiple aircraft are on frequency. “Climbing flight level 350, Air Canada 456” is correct. “Climbing flight level 350” by itself leaves ATC guessing.
These phrases are not standard in aviation radio communication. Do not use them. Simply end your transmission with your callsign.
Always double-check which ATIS information you have before contacting ATC. If you say “information Bravo” but the current ATIS is Charlie, ATC will ask you to get the updated information, which delays everyone.
Speak at a normal, measured pace. Controllers are often handling multiple aircraft and need to understand you clearly. If English is not your first language, speaking slowly is even more important - and perfectly normal. Clarity always beats speed.
If you blank on the correct phraseology, just say what you need in plain English. “Air Canada 456 needs to descend” is perfectly fine. ATC will work with you. The worst thing you can do is sit in silence and not communicate at all.

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Quick Reference: Call Structure

Every radio call follows the same basic structure:
  1. Who you are calling: “Toronto Ground”
  2. Who you are: “Air Canada 456”
  3. Where you are (if relevant): “Gate Charlie 32” or “Flight level 350”
  4. What you want: “Request pushback” or “Request IFR clearance to Montreal”
  5. Additional info: “With information Bravo”
After the initial call, subsequent transmissions are shorter - just the readback or request followed by your callsign.

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Next Steps

ATC Interaction

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