Radar and ARPA Manual

ARPA - ACCURACY AND ERRORS 379

9.63.4 Comparison ojrelative and true vectors

Given that one or other of the vectors can be affected by

input errors in a way which may be dependent on the

tracker philosophy, it is important to stress the need for

the observer continuously to compare one data source

with another to ensure that, in all cases, indications given

from relative vectors and true vectors sensibly agree.

9.6.4 The effect on the PPC of

incorrect data input

9.6.4.1 Errors in speed input

PPCs would appear

here if own ship's

speed used in their

calculation is greater

than the correct value

4

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0

PPC ...