Complete DSC Distress Workflow

When grave and imminent danger requires immediate assistance, lift the cover, select the nature of distress if time permits, and press and hold the distress control until the set confirms that the alert has been sent. Do not tap and release it. The alert should carry the vessel's MMSI and, when the radio is receiving valid GNSS data, position and time. A stale or absent position input makes the voice position even more important.

On receipt of a DSC acknowledgement, or after about 15 seconds, transmit the MAYDAY call and message on Channel 16. Give MAYDAY three times; vessel name three times; call sign or other identity and MMSI; then MAYDAY once, identity, position, nature of distress, assistance required, persons on board, and useful hazards or survival information. End with OVER and listen. If the situation changes, update the controlling station rather than allowing an obsolete message to govern the response.

The skipper should allocate tasks before pressing the button where time allows: one person controls the vessel, one transmits, one verifies and writes the position, and one prepares survival or recovery equipment. If the radio operator must leave the set, hand over the log and the exact last transmission. Preserve Channel 16 for the distress exchange and follow the Coastguard's channel instructions.

A strong command answer includes the failure branch. If DSC is unavailable, make the voice MAYDAY on Channel 16. If VHF contact is not achieved, use other available alerting appropriate to the equipment and area—such as EPIRB, PLB, another radio or satellite device—while continuing the immediate actions that protect life. Communications support the emergency plan; they do not replace damage control, recovery, firefighting, or abandonment preparation.