
RADAR PLOTTING
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result in an error in the directly obtained
answer, i.e. the course and speed of the target.
Note. If this error is repeated when laying off
WO the CPA of the target will in fact be
correct,
(iv) Perhaps the most disconcerting product of this
plotting technique is the temporary nature of
the apparent-motion line. (Figure 7.7). It is
essential to appreciate that the 'displayed' CPA
relates to only one own ship position, after
which the apparent motion line can be at worst
misleading. Where a number of targets are
being plotted on the same sheet, apparent-
motion lines can relate to different own ship
positions.
In general,