Entry & progression
This certificate is any operating area. That phrase is only worth anything if you can plan an ocean crossing properly. The plan is the master's document. You may delegate the drafting; you never delegate the responsibility.
The four stages
- Appraisal. Gather everything before you decide anything. Charts and publications for the whole route, corrected. Routeing guides, ocean passage publications, pilot charts and climatic data for the season. Load line zones. Traffic separation schemes. Piracy and security areas. Emission control and discharge areas. Draft, air draft, under-keel clearance. Fuel range with a real reserve, not an optimistic one. The vessel's own limits: sea state, motion, the SMS.
- Planning. Lay the tracks. Great circle where the saving justifies it, rhumb line where it does not, composite great circle where a limiting latitude bites. Waypoints that make sense to a tired watchkeeper at 0300. No-go areas marked. Abort points and contingency anchorages named — not assumed.
- Execution. Adjust for what the appraisal could not know: the actual forecast, the actual ETA, the actual guest movements, the actual fuel burn.
- Monitoring. Fix, cross-check, parallel index, watch the set. Every position from one source is a rumour.
Weather routeing
A yacht is not a bulk carrier and the objective is not always least time. Least time may be the worst possible track for a vessel with twelve people aboard who paid a great deal of money not to be thrown across a saloon.
- Shore-based routeing services give you a recommended track and daily updates. They do not command your vessel. Their advice is an input, not an order — and the liability for taking it stays with you.
- On-board routeing using GRIB data and your own performance curves gives you control and immediacy. It is only as good as your discipline in updating it.
- Motion, not just wind. Swell period against your natural roll period is what makes guests ill and crockery fly. A 25-knot beam sea with a long swell can be far more punishing than 35 knots on the bow.
- Tropical systems. Plan to be nowhere near them. Give sea room early, when it costs you a day. Later, it costs you the vessel.
The pressure that actually kills yachts
Almost nothing in commercial shipping compresses a master like a charter schedule. The guests fly into Palma on Saturday. The owner is expecting the vessel in Antigua for Christmas. Everyone aboard knows what the calendar says, and the calendar does not know what the barometer says.
WARNING — The plan is not a contract A passage plan is a considered intention, prepared in a warm office with good coffee, using the best information available at the time. When the information changes, the plan changes. A master who follows a plan into weather because the plan said so has confused a tool with a duty. Deviate. Log why. Tell the office afterwards, not before.
Fuel is a planning input, not an afterthought
Yachts are thirsty and their range figures are usually quoted at economical speed in flat water. Plan the passage at a speed you can actually hold, add a margin for heavy weather consumption, add a diversion, and then decide whether you can make the crossing. Bunkering options mid-ocean are, famously, limited.
And check the tanks against the plan, not against the gauges. Slack tanks are also a stability problem — Lesson 4.1.