This plotter is made from styrene vinyl plastic - don't leave it in the sun! It measures about 13-1/4" long.
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The American-style navigation plotter/protractor
is standard issue for lower latitudes where the meridians of
longitude are more parallel to each other. In northern latitudes,
where the meridians slope toward each other, these plotters become
more difficult to use due to visual illusions (it's harder to line
the plotter up with the meridians). Everything has its place! In
northern latitudes (for example, in Canada or Scandinavia),
aviators tend to prefer the Douglas parallel-rule plotter
(otherwise called the Douglas Protractor) for
measuring tracks because of the visible pie-shaped convergence of
the meridians toward the north pole.
This plotter is made from styrene vinyl plastic - don't leave it in the sun! It measures about 13-1/4" long. |