User`s guide

Chapter 14: RayTech advanced features 143
14.5 Polar plotting
This section explains how to use RayTech’s Polars tool to analyze and fine-
tune your boat’s performance. Intended primarily for the experienced
sailor, polar uses a group of variables (such as apparent/true/current
corrected wind angles, boat speed, heel and pitch, etc.) to determine what
heading you should set your boat on to achieve the best target boat speed
under varying wind conditions. Analysis results are displayed using several
graph plots and data matrices, which can be edited to suit your needs. A
typical polars plot screen is shown below.
Note: Baseline polars for your individual vessel may be available from the
vessel’s designer/manufacturer.
Data collection
The accuracy of any analysis presented by the polars tool is dependent on
the volume and accuracy of the data collected. There are two primary areas
within the polars application where you can enter and modify data:
•The Polar tab - this displays the polar parameters screen, which
contains variables/ values used to plot the polar graph.
•The
Data tab - this displays the data tests screen, which enables the
input of advanced, boat/weather performance-related information that
you can use to further fine-tune the analysis.
These screens come pre-loaded with default data, however, it is essential
to replace as much of this information as possible with real performance/
atmospheric -specific data. You can use RayTech’s Data Trak and Data
Logging functions to record a wide variety of performance-related data
that is ideal for use with these screens. Data from these screens can also
come from such sources as your boat’s manufacturer and local nautical
organizations.
Entering and editing data
Data is entered using the polar and data parameters tabs.
Polar parameters
To edit the polar parameters:
1. Click
Polar tab in the Polar Plot dialog box.
2. Replace as much of the default data as possible with actual data that
you have collected. You can modify the default values shown, or load
an existing polar parameters file. To modify the values shown, refer to
Step 3.
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