Module 6 - Distress & Mayday
Mayday Relay
What you will learn
Recognise when distress information must be relayed, identify the relaying station and pass the casualty's message accurately without inventing facts.
MAYDAY RELAY tells listeners that the transmitting station is passing distress information for another vessel or person. The relay must preserve the source message and reach an appropriate coast station without obscuring a better-placed response.
The MCA small-craft procedure requires a received, unacknowledged distress message to be relayed to an appropriate coast station by any available means. The ITU Radio Regulations give the radiotelephony relay opening: MAYDAY RELAY three times; the addressed coast station or ALL STATIONS as appropriate three times; THIS IS; the relaying station name three times; its call sign or other identification; and its MMSI when the initial alert was sent by DSC.
The relay is followed, as far as possible, by the information contained in the original distress alert or message. Separate what you heard from what you observed. If the position or identity was incomplete, say so rather than filling the gap. Time-stamp information where delay or movement matters.
Address an appropriate coast station or rescue coordination centre where reliable contact can be established. An all-stations voice relay is not the automatic first choice when a direct route exists; the ITU procedure treats it as appropriate after continued difficulty contacting shore. Ensure the relay does not interfere with a station better placed to render immediate assistance.
Worked example
Fictional partial relay opening addressed directly to Westhaven Coastguard; it is a structure example, not a complete live transmission.
- 1MAYDAY RELAY, MAYDAY RELAY, MAYDAY RELAY.
- 2WESTHAVEN COASTGUARD, WESTHAVEN COASTGUARD, WESTHAVEN COASTGUARD.
- 3THIS IS NORTH STAR, NORTH STAR, NORTH STAR; [own call sign and, where applicable, own MMSI].
- 4Pass the original casualty identity, position, nature, assistance, persons and useful information as received; identify any uncertain group.
Sense check: The opening identifies North Star as the relaying station, not the casualty, before the original distress information is passed.
Relay facts, not a reconstructed story
You hear a weak voice Mayday from yacht Blue Dawn with a position and flooding report, but no Coastguard acknowledgement is heard. Your vessel can contact the Coastguard clearly.
1. Capture the source
Write the casualty identity, position, time, nature, assistance and people exactly as received, marking uncertain groups.
2. Choose the route
Contact the appropriate coast station by the best available means without covering the casualty's Channel 16 traffic.
3. Identify the relay
Use MAYDAY RELAY, identify your own relaying station, then pass the casualty information with uncertainties intact.
Sense check: The receiving controller should be able to distinguish the casualty's reported facts, your observations and any information you could not verify.
Common mistake or limitation
- Presenting the relaying vessel's identity as though it were the casualty identity.
- Improving an unclear position or people count by guessing.
- Broadcasting to all stations automatically when an appropriate coast station can be contacted reliably.
Recap
- Relay an unacknowledged distress to an appropriate coast station by any available means.
- Identify the relaying station before repeating the original distress information.
- Preserve uncertainty and avoid interfering with a better-placed response.
Optional quick check
Section 9 of 10
What is the safest rule when a relayed position group was unclear?
Sources and factual review
Reviewed 1 September 2026 - Compass Revision editorial review.
Continue studying Distress & Mayday
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