Where candidates go wrong
Asked 'is this chart fit to use?', candidates recite chart symbols. The examiner wants a process: right chart, right scale, right edition, corrected, datum understood, and warnings applied. The second trap is treating ECDIS as a licence to stop thinking. Say what the primary means of navigation is on your yacht and how you know.
Governing: Appendix 11 Section 4; AMSA 243 'Navigation — charts and publications'; STCW Code A-VIII/2 Part 4-1; Marine Order 74 s 8.
Choosing and checking the chart
| Check | What you say to the examiner |
|---|---|
| Scale | Largest scale on board suitable for the area (STCW A-VIII/2 para 47) |
| Edition and corrections | Latest edition; corrected to the last Notice to Mariners received; record of corrections kept |
| Datum | Horizontal datum (WGS84 for GNSS positions) and vertical datum for soundings and heights, read from the title block |
| Source data | Check the source diagram or zones of confidence; old survey = wider margins |
| Temporary and preliminary notices | Applied in pencil and removed when cancelled |
| Warnings | Current NAVAREA X and AUSCOAST warnings plotted or noted in the passage plan |
On an Australian coastal passage the vertical datum on modern charts is normally lowest astronomical tide, but read the title block rather than assume, particularly on older or foreign-produced charts of Pacific islands a yacht may visit.
Publications a watchkeeper uses
Be able to say what each one is for and how it is kept up to date: sailing directions, list of lights, tide tables and tidal stream atlases, radio signals lists, the Mariner's Handbook, chart catalogue and the Notices to Mariners themselves. The examiner will not ask for page numbers; he will ask where you would look for a port's VHF working channel, or for the characteristics of a light you cannot identify.
Maritime safety information in Australian waters
- AMSA, as RCC Australia and NAVAREA X coordinator, issues navigational warnings.
- The Bureau of Meteorology, as METAREA X coordinator, issues meteorological warnings and forecasts.
- Delivery is by Inmarsat SafetyNET and Iridium SafetyCast, supplemented by HF voice broadcasts from Wiluna (WA) and Charleville (Qld).
- Warnings go to NAVAREA X and AUSCOAST areas A to H; a weekly summary of warnings in force is issued on Thursday at 0000 UTC.
- AMSA reminds masters that EGC and HF receivers must be correctly configured, even in port (Marine Notice 05/2023).
CAUTION — The EGC receiver nobody set up A yacht arriving from the Med often still has its EGC receiver set for NAVAREA III. Check the NAVAREA and coastal areas selected before you rely on 'no warnings received'.
ECDIS on a yacht
Many superyachts carry ECDIS; some carry chart plotters that are not ECDIS at all. Know the difference and what the flag and class have approved as the primary means. MO 74 s 8(2) requires the ECDIS-trained endorsement if you keep watch on a yacht fitted with ECDIS. Be ready to discuss safety contour and safety depth settings, over-reliance on a single sensor, scale and overscale warnings, and the backup arrangement. The detail sits in the ECDIS course; the examiner wants to hear that you check alarms are set and that the backup is real.
Command-level obligation
The officer of the watch owns the chart in use. If it is not corrected, not the largest scale, or not understood, you say so to the master before the passage, not after the grounding.