Aeronautical Radiotelephony Communications Procedures
The core phraseology system
Aeronautical radiotelephony is built on standardised phraseology so that transmissions are short, unambiguous, and predictable. Candidates must know the structure of a transmission: station called, station calling, message. Callsigns must be used correctly, with full callsigns until the ground station approves an abbreviated form.
Priority and emergency communications
Know the three distress and urgency signals and when each applies: MAYDAY for distress (grave and imminent danger requiring immediate assistance), PAN PAN for urgency (a condition concerning safety but not requiring immediate assistance), and the use of SECURITE for safety messages. Distress has absolute priority. Traps include using PAN PAN for a situation that is genuinely distress, failing to state the nature of the problem and intentions, and forgetting to cancel the distress or urgency condition when it ends.
Readback and clearance discipline
Safety-related clearances must be read back. This includes levels, headings, speeds, frequencies, runway and approach clearances, and conditional instructions. A frequent question trap is the conditional clearance - the readback must include the condition, not just the clearance.
Worked example
A controller says: "ABC, cleared to land runway 27, wind 270 at 12." Correct readback: "Cleared to land runway 27, ABC." The wind need not be read back, but the clearance must be. If the clearance were conditional - "after the departing aircraft, line up runway 27" - the readback must repeat the condition.
Radio discipline
Listen before transmitting, keep transmissions brief, and use standard words such as ROGER, WILCO, AFFIRM and NEGATIVE correctly.