Distress Alerting from a Sinking Yacht Offshore
A 60-foot sailing yacht with four persons aboard is 60 nautical miles east of Cape Hatteras at 0230 local time. She has just been holed by a submerged container and is taking on water faster than the manual pumps can handle; the engine will not start. Equipment: a 25 W VHF transceiver with DSC (MMSI programmed, GPS position fed to the controller), a 150 W MF/HF SSB with DSC on 2187.5 kHz, a 406 MHz float-free EPIRB still sitting in its bracket, and one 5 W handheld VHF. There is no other vessel in sight. The nearest coast station is about 90 nm away, and the VHF set has been reaching ships at roughly 20 nm. Water is now above the cabin sole and the crew is preparing the liferaft.
1. In what order should the crew use the EPIRB, the VHF DSC alert, the MF/HF DSC alert, and voice, and why?
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These assets reach different audiences, so they are used in parallel, not in a queue.
- EPIRB first, manually. It is still in its bracket, so it has not water-activated. A 406 MHz alert reaches the Cospas-Sarsat satellite system in minutes and carries the registered identity; it works whether or not anyone is listening on any band.
- VHF DSC distress alert on channel 70 next. Every DSC-equipped vessel and coast station within roughly 20–30 nm is alarmed automatically and receives the MMSI plus the GPS position.
- MF DSC alert on 2187.5 kHz. The 150 W set reaches much further than VHF - easily the 90 nm coast station and ships out to 100 nm or more.
- Voice MAYDAY on channel 16, then on 2182 kHz, as the follow-on to each DSC alert.
Reasoning: with water rising and the nearest coast station 90 nm away, waiting for an answer before using the next asset spends time the crew does not have. Each alert costs seconds and covers a completely different set of listeners. Note also that voice-only on VHF ch 16 reaches at most ~20 nm here - it cannot be the primary alert.
2. Write the MAYDAY call and state what must be in it and what the crew should do in the 60 seconds after transmitting.
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"MAYDAY, MAYDAY, MAYDAY. This is [vessel name, three times], MMSI 3xxxxxxxx, MAYDAY [vessel name]. My position is 35 degrees 12 minutes North, 074 degrees 30 minutes West, or 60 miles east of Cape Hatteras. I have been holed by a submerged container and am taking on water; I am sinking. I require immediate assistance. Four persons on board, preparing to abandon to liferaft. Over."
Must-include items, in order of what a rescue coordination centre needs: distress signal and identity (spoken three times), position (latitude/longitude, plus a range and bearing from a known point as a cross-check), nature of distress, number of persons, type of assistance required, and any other useful detail (EPIRB on 406 MHz, liferaft, sea conditions).
After transmitting: do not sit in silence. Switch to a working channel if a station responds, keep a listening watch on 16 with another set or the handheld, keep the EPIRB running, put the grab bag, water, handheld, and flares in the liferaft, and only abandon when the vessel actually goes under or a rescuer directs it. Send a short update if the situation changes materially.
3. No reply comes for eight minutes. Then a merchant vessel 18 nm away answers on channel 16 while the coast station is still 90 nm out. How should the radio traffic be handled?
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Take the reply, then move the working traffic off channel 16 (to channel 06 or another ship-to-ship channel) so that 16 stays clear for other distress traffic - but keep a listening watch on 16 with the handheld or a second set.
Pass to the merchant vessel: position and drift, nature of the casualty, number of persons, and that a liferaft may be launched; ask for its ETA, and keep the exchange short - say "OVER" and let them talk. Confirm that the merchant vessel has relayed the MAYDAY to the coast station (a MAYDAY RELAY is appropriate if the coast station has not acknowledged).
Judgement points: the 406 MHz EPIRB stays on until rescue forces say otherwise; do not cancel or downgrade anything - the situation is still a distress, not a urgency; do not let a single responding ship stop you from also keeping the coast station informed; conserve the handheld battery by agreeing a schedule (e.g., every 15 minutes). If the vessel sinks, the floating EPIRB goes with the liferaft and continues transmitting.