MAYDAY vs PAN-PAN: which radio call do you use?
- 1MAYDAYgrave and imminent danger
- 2PAN-PANurgent, not yet grave
- 3SÉCURITÉsafety of navigation or weather
MAYDAY is the spoken distress signal: a vessel or person is in grave and imminent danger and requires immediate assistance. PAN-PAN is the urgency signal: a very urgent message about the safety of a vessel or person that does not yet justify distress. Each prefix is spoken three times.
Related terms
How it works
The prefixes rank the traffic. MAYDAY outranks everything: it commands radio silence and obliges vessels that hear it to assist if they can. PAN-PAN comes next for serious situations short of grave and imminent danger—engine failure with the boat drifting toward danger, or an injured crew member needing medical advice. SÉCURITÉ, the third level, prefixes safety-of-navigation and weather messages such as gale warnings or a drifting hazard.
The working pattern on VHF: a DSC-equipped radio can first send a digital alert on channel 70 carrying your MMSI and position, then the voice call follows on channel 16—the prefix three times, vessel name, position, the nature of the problem, and the help needed. Situations move on the ladder: a PAN-PAN can be upgraded to MAYDAY if danger becomes grave and imminent, and any call should be formally cancelled once resolved.
Where the words come from
All three prefixes are French, chosen when radiotelephony went international: MAYDAY from m’aider (help me), adopted as the spoken distress signal by the 1927 International Radiotelegraph Convention; PAN-PAN from panne (a breakdown); and SÉCURITÉ (safety). The three-times repetition exists so a weak or clipped transmission still identifies its priority beyond doubt.
On the water
- Water is rising faster than the pumps can cope: “MAYDAY, MAYDAY, MAYDAY,” then vessel name, position, the distress, and people on board.
- Engine dead and drifting toward a shipping lane with time in hand: “PAN-PAN, PAN-PAN, PAN-PAN” warns all stations that help may be needed.
- A coast station broadcasts “SÉCURITÉ” three times before a gale warning and a report of a drifting container.
Common mistake
Never send a practice or hoax MAYDAY. False distress calls divert rescuers from real emergencies and are a serious federal offence that can bring imprisonment, heavy fines, and liability for the cost of the search. When the situation is serious but not yet grave and imminent, PAN-PAN is the honest call.
Remember it
French under the hood: m’aider—help me now—outranks panne—a breakdown.