
RADAR PLOTTING
313
Figure 7.27 The use of
a
rotatable plotting surface
(a) Before or during alteration of course
(b) After rotation of the plotter
7.9 Manual plotting - accuracy and
errors
The error in the result from any computation depends
upon the accuracy of the data used. The intrinsic sources
of error in the radar system relate to the measurement of
ranges and bearings. Other data needed to complete the
radar plot and subject to error are own ship's course and
speed, and the plotting interval. Also, there are of course
personal errors and blunders. While a
constant
(or sys-
tematic) error in input will result in a constant error in
th