Why this matters at command level
As Master, the duty to report dangers to navigation rests with you personally. SOLAS Chapter V Regulation 31 places an obligation on the master of any vessel who encounters a danger to navigation to communicate that information by all means available to ships in the vicinity and to the competent authority. Understanding the 'why' behind each step is what separates a confident oral answer from a recited list.
What triggers the obligation
The obligation arises when you encounter any of the following:
- A dangerous ice, derelict, or other direct danger to navigation
- A tropical storm, or sub-freezing air temperatures causing severe icing on superstructures
- Winds of Beaufort force 10 or above for which no storm warning has been received
- A dangerous depth sounding inconsistent with charted data
The trigger is encounter or observation — you do not need to be in immediate danger yourself. The obligation is to report what others cannot yet see.
The reporting sequence and the reason behind each step
1. Warn ships in the vicinity first. Broadcast on VHF DSC and voice, and on MF/HF if range demands it. Other vessels may be closer to the hazard than the shore authority. Getting a warning to sea traffic is the immediate life-safety priority.
2. Report to the competent authority. This is typically the nearest MRCC or coast radio station. The authority then takes responsibility for issuing a Navigational Warning through the NAVTEX/SafetyNET system — the formal mechanism by which the information reaches all ships in the area systematically and is logged.
3. Include all the information a navigator needs to act. The SOLAS V/31 message format requires: your vessel's name; your position; UTC time of observation; and a clear description of the danger. Without time and position the report cannot be plotted. Without a description it cannot be assessed. Think of it as completing the chart for someone who cannot see what you saw.
4. Record the report in the deck log. This confirms compliance, captures the exact wording sent, and creates the evidential record if the danger later causes an accident. At command level, the log entry is your professional protection.
Flag State context
For UK-flagged yachts, the core regulatory source is SOLAS V/31; MSN 1858 is the domestic instrument that places this on Red Ensign Group vessels. In your oral exam, cite SOLAS V/31 as the primary source and MSN 1858 as the UK implementing notice.
A practical point examiners probe
There is no discretion — reporting is mandatory, not advisory. Examiners will ask what you do if communications equipment is limited. The answer is: use every means available (VHF, MF/HF, satellite, signal to a passing vessel) and document what you attempted.