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2 Voyage planning
The process “Voyage planning" generates the output data stream “current voyage plan” from input data
from differing sources. The requirements on this output datum are defined by Process 2 “Monitoring
and executing the voyage” (see [2]) - the main user of this datum. Since track control during voyage
execution in particular relies on the current voyage plan, the latter must fulfil special safety requirements.
Amongst other things, this means that the current voyage plan must possess an attribute which verifies
successful checking of this data stream.
Voyage planning consists of three sub-processes:
1. Drafting the voyage plan
2. Checking the voyage plan
3. Administering the voyage plan.
The introduction of a sub-process for administering voyage plans makes clear that voyage planning can
also be carried out in “asynchronous” manner, i.e. the drafting of a voyage plan and its use for voyage
execution do not necessarily have to be directly successive in terms of time. The “planning phase” may
instead take place at a time well before the “execution phase”. In this case, particular attention should
be paid to questions of topicality, particularly on the part of the boundary conditions considered during
planning (see below).
The following input data are processed by the process ‘Voyage planning”:
1. Timetable
2. Voyage plan data
3. Hydrographic data
4. Meteorological data
5. Geographical data and reference parameters
6. Ship data and ship parameters
These input data can be divided into two categories:
1. Set parameters: “Timetable” and “Voyage plan data”.
These data streams contain set values which supply general parameters for detailed voyage planning,
e.g. voyage objectives, arrival times, set courses and speeds for certain voyage sections. Voyage plan
data and timetables are essentially distinguished here by the particular time horizon considered;
I The timetable is generally available before starting the voyage. On the basis of the data in
the timetable, complete planning is undertaken from the departure port to the destination
port. The result of the planning is available at the start of the voyage.