Module 6 - Distress & Mayday
When to Use Mayday
What you will learn
Recognise the distress threshold early and choose Mayday when a vessel or person is in grave and imminent danger and immediate assistance is required.
Mayday is a decision about the danger and the help needed now. It is not reserved for a perfect diagnosis, and it must not be used merely to make an ordinary request sound important.
The MCA small-craft procedure defines the threshold as grave and imminent danger where assistance is required. Fire that cannot be controlled, uncontrolled flooding, a person in the water who is not recovered, or an imminent need to abandon may meet that threshold. The facts and rate of deterioration matter; a label such as 'engine failure' does not decide the priority on its own.
PAN-PAN is the urgency signal for serious concern about the safety of a person or vessel when the distress threshold has not been reached. If an urgency situation deteriorates into grave and imminent danger requiring immediate assistance, upgrade it to Mayday. Do not delay the higher-priority call merely to preserve the priority chosen earlier.
The spoken structure is important, but the first skill is judgement. A learner who can recite MAYDAY yet waits for perfect information during rapidly rising water has not learned the safety decision. State what is known, give the best usable position and update the coordinating station as the situation changes.
Choose the priority from the changing risk
A yacht has lost propulsion near clear water. Ten minutes later it is being set towards rocks, the anchor has not held and there is no safe margin left to solve the problem without outside help.
1. Classify the present danger
Do not classify from the original engine fault. Assess the current approach to danger, the remaining time and whether immediate assistance is now required.
2. Escalate without apology
If the situation is now grave and imminent, use Mayday even if an earlier call or plan treated it as urgency.
3. Keep managing the casualty
Delegate the call where possible while the crew continues lifejackets, damage control, position monitoring and preparation for the next safe action.
Sense check: The selected priority should describe the danger and assistance needed now, not the name of the first equipment failure.
Common mistake or limitation
- Waiting for an exact diagnosis or perfect position while the danger becomes immediate.
- Using Mayday to obtain attention for a routine problem that does not meet the distress threshold.
- Refusing to upgrade PAN-PAN when the situation has materially deteriorated.
Recap
- Mayday means grave and imminent danger with immediate assistance required.
- Priority can change as the incident develops.
- Call with the best reliable information available, then update changes.
Optional quick check
Section 1 of 10
A disabled yacht is being driven onto rocks, cannot arrest the approach and needs immediate outside help. Which priority now fits?
Sources and factual review
Reviewed 1 September 2026 - Compass Revision editorial review.
Continue studying Distress & Mayday
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