1. Define the voyage and its alternatives
The RYA recommends considering boat and crew capabilities, hazards and alternatives, including a passage taking longer than expected. A plan is therefore more than a line between two ports.
Prepare a sheet for each leg: objective, arrival constraints, information needed, fallback options and possible reasons to abandon it. A purely arithmetic example: 600 nautical miles at an average 5 knots gives 120 hours, or five days. That result allows for neither diversion, calm nor slowing down. Recalculate using several hypothetical speeds to show how sensitive duration is, without treating those examples as forecasts of the boat’s performance.
References for this section : RYA — Passage planning
2. Read a dated forecast for the right area
Météo-France publishes marine bulletins and warnings for its covered areas. NOAA services also provide textual forecasts by ocean area. Select a product that matches the sailing area, geographical coverage and valid period.
For each download, record issue time, validity, area, provider and the next expected update. Arrange access to the bulletin before leaving a reliable connection. Saving a screenshot does not keep it current: at a watch handover, explicitly say whether the information has been updated or whether the crew is still using an older forecast. Keep dates and time zones visible so different products are not compared at different forecast times.
References for this section : Météo-France — Météo marine : côte, large et BMS · NOAA NWS — Marine text forecast products
3. Read charts and files without false precision
NHC gridded marine products include wind, gusts, significant wave height and hazards. Their description specifies spatial resolution and time steps: a grid is a defined product, not a continuous observation of every patch of sea.
Compare what the tool displays with the bulletin and observations aboard. When they disagree, record what is changing instead of automatically choosing the most pleasant scenario. A very precise calculated route can still rest on weak assumptions. Ask: “What would we change if the wind arrived earlier, stronger or from a different direction?”. Write that decision down while there is time to consider it, rather than waiting for a display to become a promise.
References for this section : NOAA NHC — Gridded marine forecasts
4. Maintain current navigational information
Shom distinguishes corrections distributed through Notices to Mariners from urgent navigational warnings; PING provides access to French nautical information. Carrying a recent chart does not remove the need to consult relevant supplementary notices.
For landfalls and possible refuges, list documents, dates and restrictions requiring checks. Move from overview scale to an appropriate scale to inspect hazards. Prepare a way to recover position and essential information if the main screen becomes unavailable. Test the backup in practice: two apps relying on the same device and power supply are not two independent systems. Record where the offline information is stored and who can access it.
References for this section : Shom — GAN et avertissements de navigation
5. Arrange an effective lookout
Rule 5 of the international collision regulations requires an appropriate lookout by sight, hearing and available suitable means. Autopilot, radar and AIS assist the crew; they do not replace the lookout obligation.
The RYA notes that there is no universal watch rota. Build a timetable around capabilities, rest, meals and other duties. Prepare instructions for calling the skipper: uncertainty about another vessel, poor visibility, changing weather, an alarm or steering difficulty. An explicit instruction to call early avoids hesitation about disturbing someone. Discuss how the rota will change if a crew member becomes unable to participate; a printed timetable cannot create rested people.
References for this section : IMO — Convention on the International Regulations for Preventing Collisions at Sea · RYA — Night boating and watchkeeping
6. Connect endurance with actual operation
The proposed passage table separates stores aboard, observed consumption and the margin retained. Record water, fuel and energy daily using consistent units and measurement methods. What matters operationally is the amount still available, not a capacity figure in a sales brochure.
Prepare one scenario with impaired charging and another with a longer passage, linking them to the energy and safety dossiers. Do not count solar production as received before it has actually been observed. Identify loads that can be reduced without sacrificing navigation and distress functions. This exercise exposes dependencies and available choices; it cannot guarantee endurance for a particular boat. Update assumptions when the measured trend differs from the plan.
References for this section : RYA — Passage planning
7. Record departure, handover and reassessment
A proposed decision sheet can use three states: ready, needs checking, departure postponed. Give each outstanding item an owner. Blocking issues come from the boat and programme: an unresolved defect, an unavailable crew member, essential missing information or conditions beyond the chosen limits.
At handover, communicate position and time, course being steered, traffic, sail plan, observed weather, system condition and the next expected decision. After the crossing, compare the plan with what happened: time differences, fatigue, consumption and difficult manoeuvres. Improve the next plan using those observations. The preferred arrival date remains a logistical aim; it must not erase an operational limit or turn an unresolved issue into something accepted by default.
References for this section : RYA — Passage planning · RYA — Night boating and watchkeeping
A good passage plan does not claim to predict the whole sea: it helps you recognise a change and decide in time.
Your practical checklist
Sources & documents
- RYA — Passage planning
Accessed 2026-11-02 - Météo-France — Météo marine : côte, large et BMS
Accessed 2026-11-02 - NOAA NHC — Gridded marine forecasts
Accessed 2026-11-02 - NOAA NWS — Marine text forecast products
Accessed 2026-11-02 - Shom — GAN et avertissements de navigation
Accessed 2026-11-02 - IMO — Convention on the International Regulations for Preventing Collisions at Sea
Accessed 2026-11-02 - RYA — Night boating and watchkeeping
Accessed 2026-11-02
