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Introduction

Effective communication between pilots and air traffic controllers (ATC) is essential for flight safety and efficiency. Standardized phraseology ensures clarity, uniformity, and minimizes ambiguity in radiotelephony (RTF) communication.

The phraseology outlined here is based on ICAO Doc 4444, 16th edition (Nov 2016) and must be used in conjunction with proper call signs.

What is Phraseology?

Phraseology refers to the structured communication used between pilots and ATC. It ensures clear and precise transmissions to reduce misunderstandings.

  • Standard phraseology applies to routine and emergency communications.
  • When standard phrases do not cover a situation, pilots and controllers should use plain language that is clear, concise, and direct.
  • Pilots must read back all clearances and instructions they receive from ATC, except in emergency situations or in cases of radio failure.

Basic Rules of Communication

  • ATC must start all transmissions with the aircraft’s call sign.
  • Pilots should end their readback with their call sign.
  • When contacting ATC for the first time, a pilot should state both the ATC unit and their own call sign.
  • Some abbreviations, such as ILS, QNH, and RVR, may be spoken as individual letters rather than using the full phonetic alphabet.

Omitted Words in Transmissions

To keep transmissions concise, the following words may be omitted if no confusion arises:

  • "Surface" (in relation to wind direction and speed).
  • "Degrees" (when giving radar headings).
  • "Visibility," "Clouds," and "Height" (in meteorological reports).
  • "Hectopascal" (when providing pressure settings).

Use of Conditional Instructions

Conditional instructions (e.g., "Behind landing aircraft, line up and wait") must follow a strict format to avoid confusion.

Format for Conditional Instructions:

  1. Identification – Aircraft receiving the instruction.
  2. Condition – The reference traffic or event (e.g., "Behind the landing Airbus A320").
  3. Clearance – The specific instruction given (e.g., "Line up and wait").
Example:

📡 ATC: "SAS947, behind landing DC9, line up and wait Runway 12."
🛩 Pilot: "Behind landing DC9, line up and wait Runway 12, SAS947."

Important: Conditional phrases must not be used for runway movements unless the controller and pilot have a clear visual of the aircraft or vehicle in question.

Transmitting Techniques

To ensure clear and understandable communication, ATC and pilots should:

  1. Listen before transmitting to avoid interference.
  2. Use a normal tone and speak clearly and distinctly.
  3. Maintain a steady speaking volume throughout the transmission.
  4. Pause slightly before and after numbers for better comprehension.
  5. Avoid hesitation sounds like "er" or "um."
  6. Keep a consistent distance from the microphone for clear audio.
  7. Depress the transmit button fully before speaking and release it only after completing the message.

Readback Procedures

Pilots must read back all safety-critical clearances and instructions. This ensures that ATC clearances are received correctly and executed as intended.

Readback is mandatory for:

  • ATC route clearances.
  • Runway instructions, including:
    • Entering, landing on, taking off from, or holding short of a runway.
    • Crossing or backtracking on a runway.
  • Runway-in-use information.
  • Altimeter settings.
  • SSR codes (Squawk assignments).
  • Level, heading, and speed instructions.
  • Transition level assignments.

Example Readbacks:

📡 ATC: "DEHBA, taxi to holding point Runway 01."
🛩 Pilot: "Taxi to holding point Runway 01, DEHBA."

📡 ATC: "DEHBA, squawk 4525."
🛩 Pilot: "Squawk 4525, DEHBA."

Additional Guidelines for Effective Communication

  • The word "IMMEDIATELY" should only be used when immediate action is required for safety reasons.
  • Avoid unnecessary courtesies like "please" or "thank you" in radio transmissions.
  • Do not use redundant words such as "this is," "over," or similar terms unless needed for clarity.
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