Open Oceans use small-scale charts, gnomonic projection ocean charts for plotting great circle routes. Load line zone charts are used to ensure Load Line rules are complied with. Ocean current charts are used to take advantage of the favourable currents.
Ice movements are noted to keep clear of them. Frontal depressions and poor visibility can restrict the northerly or southerly latitudes for navigation.
Seasonal Tropical Revolving Storms (TRS) where encountered are to be avoided and enough searoom provided to steer clear of the same. Weather routing services are to be followed.
Landfall targets are identified with their likely radar/ visual ranges. In respects of lights, their rising and dipping ranges and arc/ colours along with their sectors are identified.
Coastal or restricted waters have limited time available in taking corrective measures.
Manoeuvring characteristics of the ship and its limitations, if any, particularly with reference to the propulsion and the steering systems must be taken into consideration before planning these passages.
Ship squat can reduce under keel clearance at speed and must be considered very carefully.
Ship routing schemes and reporting systems along with route and vessel traffic services should be strictly followed.
Coastal weather bulletins including gale warnings may require changes in the passage plan.
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