Module 18 - Signals & Communications

MAYDAY Voice Format

What you will learn

Build and deliver a MAYDAY message that gives unambiguous identity, position, distress, assistance and persons on board before secondary detail.

A fixed order reduces omissions under pressure and lets the receiving station write the message. Prepare a position card before the emergency whenever possible.

A clear voice MAYDAY follows a predictable structure: MAYDAY repeated three times, vessel name repeated three times, call sign or MMSI if available, position, nature of distress, assistance required, number of persons on board, and any other useful information.

Position must be unambiguous. Latitude and longitude are best when available, but a bearing and distance from a known charted object is acceptable if that is the clearest position you can give. In pilotage waters, the harbour entrance, buoy, sector light, or headland reference may help rescuers identify the area quickly.

Worked example

The operator prepares a message card for yacht Meridian, call sign MABC2, MMSI 232123456, at 50° 42.6′ N 001° 12.4′ W, taking water with four persons aboard.

  1. 1Write the identity and position before transmitting; cross-check the N/W directions and current time.
  2. 2Make the MAYDAY call and identification, then repeat MAYDAY and the vessel identity as the published procedure shows.
  3. 3Give the position, nature of distress, assistance required, persons on board and the injured-person detail in short groups.
  4. 4End with OVER, listen and log the acknowledgement or instruction.

Sense check: The message remains useful even if the transmission ends after the essential position, distress and assistance information.

MAYDAY Voice Format
IdentityName, call sign or other identity, MMSIWill the receiver know which station is in distress?
PositionChecked latitude/longitude or unambiguous charted referenceAre directions and reference complete?
DistressWhat is happening and its trendDoes the wording match the present danger?
Response needAssistance, persons on board, useful hazardsCan the coordinator decide what to send?

Turn a cockpit report into a writable message

The yacht is taking water near a traffic route. The operator has the vessel name, call sign, MMSI, a checked latitude and longitude, four persons on board and one injured crew member.

  1. 1. Identify

    Use the MAYDAY call, vessel name, call sign or other identity and MMSI in the published order.

  2. 2. Locate

    Give a complete, checked position early enough for the receiver to act.

  3. 3. Describe and request

    State the distress, assistance required, persons on board and concise useful hazards or survival information.

Sense check: Another crew member can write the identity and position without guessing a hemisphere, reference point or time.

Common mistake or limitation

  • A long story before the position consumes airtime while the receiver still does not know where to send help.
  • Coordinates without North/South and East/West, or an unnamed bearing reference, are ambiguous.
  • Do not invent the persons-on-board count or the casualty condition; report what is known and update it.
  • A memorised script is not enough if nobody can find the vessel identity and current position under pressure.

Recap

  • Identity and position come before extended detail.
  • State the distress, assistance required and persons on board plainly.
  • Use a written message card and cross-check safety-critical numbers when time permits.
  • Listen and update the controlling station as the incident changes.

Optional quick check

Section 3 of 18

Which addition most improves ‘We are near the headland and taking water’?

Choose one answer
Sources and factual review

Reviewed 20 August 2026 - Compass Revision editorial review.

Continue studying Signals & Communications

This public lesson is part of Revision Module 18. Full revision access adds the guided Learn, Practise and Test flow, flashcards and revision progress.