Distress and Urgency Signals (MAYDAY/PAN PAN) and Procedures

090-05-01Pablo Asensio Martínez2026-04-012 min

Definitions

  • DISTRESS (Socorro): A condition of being threatened by grave and imminent danger and of requiring immediate assistance.
    • Signal: MAYDAY (Spoken three times).
  • URGENCY (Urgencia): A condition concerning the safety of an aircraft or other vehicle, or of some person on board or within sight, but which does not require immediate assistance.
    • Signal: PAN PAN (Spoken three times).

Priorities of Messages

Aeronautical messages are processed in the following order of priority (ICAO Annex 10):

  1. DISTRESS (MAYDAY).
  2. URGENCY (PAN PAN).
  3. Direction Finding (e.g., QDM requests).
  4. Flight Safety (ATC Instructions).
  5. Meteorological (METAR, SIGMET).
  6. Flight Regularity (Company messages).

Distress Procedures (MAYDAY)

Making the Call

The distress call should be made on the air-ground frequency currently in use. This ensures the controller and surrounding traffic are immediately aware. If unable, use 121.5 MHz (Guard).

Format:

  1. MAYDAY, MAYDAY, MAYDAY.
  2. Name of Station addressed.
  3. Call Sign.
  4. Nature of distress (e.g., Engine fire).
  5. Intentions (e.g., Emergency landing).
  6. Position, Level, Heading.

Mnemonic: NIP (Nature, Intention, Position).

Imposing Silence

Other stations or the controller can impose silence to ensure the channel is clear for the distress traffic.

  • Phrase: "STOP TRANSMITTING - MAYDAY".
  • Termination: "DISTRESS TRAFFIC ENDED".

Action by Other Stations

Stations aware of distress traffic must:

  • Maintain silence on the frequency.
  • Monitor the situation.
  • Only transmit if they can render assistance or if permitted by the controlling station.
  • ATC may transfer other traffic to a different frequency to leave the distress aircraft on the current one, or move the distress aircraft to a discrete frequency.

Urgency Procedures (PAN PAN)

Used for situations like a medical emergency on board, engine failure (if flight can proceed safely for now), or getting lost.

  • Call Format: "PAN PAN, PAN PAN, PAN PAN".
  • Includes: Name of station, Call sign, Nature of problem, Intention, Position.
  • Medical Transports: "PAN PAN MEDICAL" is reserved for protected medical transports (e.g., ambulances carrying organs/patients protected under conventions) but general medical emergencies on board use "PAN PAN" (often followed by nature of medical issue).

SSR Transponder Codes

  • 7700: Emergency / Distress ("Going to Heaven").
  • 7600: Radio Failure ("Radio fix").
  • 7500: Unlawful Interference ("Man with a knife").