MaxSea Operator Manual version 12.6 - Furuno USA

Professional Weather Routing
4 - all courses indicated by isochrons are optimal courses; they simply show courses in accordance with
varying criteria (bearing more to the north, more to the south, etc.) and thus with varying proximities to
the target waypoint.
If a routing has been plotted and you then decide to launch a second routing (once you have changed the
weather file or opened a different polar, or to plot the course of one or more competitors, etc.), the program
saves a track in the User file which corresponds to the initial routing and which contains all its parameters
(times at certain points in the passage, wind force and direction, etc.). sees User data and High level
functions for the management of such data (for example, how to remove a track) and access information at
any point on the plotted course (by double-clicking at the desired point with the Finger tool).
Initializing Weather Routing
To access to the modifying routing parameters select the [Calculate Routing] function from the
[Performance] menu
The Initialization Dialog is displayed and allows you to enter the desired parameters in the corresponding
input texts.
1 - Position and Date zone: allows you to change the date study
2 - Graph zone allows you to define your graph Depending on :
The Angle Study : Routing is carried out either side of the great circle; you can specify, to the nearest 10°,
the minimum angle (to be shown as a negative figure to the left of the great circle) and the maximum angle
(a positive figure to the right of the great circle). Values of -60° and +60° are adequate in most cases
(default value.)
Isochron Number :The program will display the number of isochrons specified in accordance with steps
entered in the routing parameters. The length (in time) of the study you are going to make will be equal (in
hours) to the number of steps multiplied by the interval between isochrons (see the next paragraph).
Interval between Isochrons: The time interval specified dictates the level of accuracy of your study; a
value which is half the value specified for time intervals in the weather file should be correct (4 or 6 hours in
the case of typical files based on 12 hour intervals). The time interval is unlimited till the end of the weather
file and the isochron interval can be reduced down to 1 minute. "00 d 02 h 00 mn"by default the interval
number is equal to 2 hours. In very changeable weather conditions you may need to use a value which is a
quarter of the one specified in the weather file in order to obtain a very precise study.
Efficiency: The efficiency can be modified to take into account speeds which are different from those
contained in the speed polar (in the case of a sea which is particularly hard to navigate, problems with the
sails, the crew being tired, equipment not working properly, etc.)
3 - Calculation Zone: allows you to choose which
Click on the OK button once you have made your modifications to launch the routing (see
the previous paragraph Launching a routing ).
Customizing Routing
Show & Hide isochrons on the chart
Isochrons may be displayed and removed at your will in order to improve the legibility of the chart:
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