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PPL Tester

Distress call: MAYDAY structure, authority and addressing

MAYDAY parts (RIC-21 6.8):

Part Job
Distress call Gets attention
Distress message Gives details; sent as soon as possible after the call

Distress call format (RIC-21 6.7):

  1. "MAYDAY" x3
  2. "THIS IS"
  3. Call sign of aircraft in distress x3
Topic Rule Ref
Who may send Only on person in command authority RIC-21 6.7
Who may send A station may also send MAYDAY on behalf of another aircraft, ship, or vehicle it becomes aware is in grave and imminent danger RIC-21 6.4(2)
Addressing Not addressed to a station; any station may answer -
Addressing No station acknowledges receipt before the distress message is sent RIC-21 6.7
Frequency First transmission on the air-ground frequency already in use TC AIM SAR 4.2(b); RIC-21 6.3
Timing MAYDAY/PAN PAN precedes the first distress or urgency communication; later ones only if necessary TC AIM SAR 4.1

Trap: MAYDAY does not precede every transmission, only the first; later ones only if necessary (TC AIM SAR 4.1).

References

Practice