
APRA-SPECIFIED FACILITIES
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When a target is 'marked' or 'designated', i.e. the
joystick and gate are used to indicate to the computer the
target about which data are required, data relating to
that target can then be read out in alphanumeric form,
i.e. range, bearing, CPA, TCPA, course and speed
(Figure 4.13). In some systems the data available also
includes the distance at which it is predicted that the
target will cross ahead (BCR) and the interval which
will elapse until this event occurs (BCT). The readout
may be on a separate tote displaying all quantities, or, in
some cases, displaying the data in sequential groups of
two items or