User's Manual Part 2

Operator Manual
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3748DOC020102 Edition: 14.JAN.2005
2.4.4 CPA/TCPA
ARPA constantly evaluates the closest point of approach (CPA) and the time to
closest point of approach (TCPA) status of each tracked target.
This CPA/TCPA zone is available with predefined values.
The CPA/TCPA values are generally ship−specific and must be adapted to the
profile of the ship.
The ship’s profile includes features such as stopping distance, sea area and
visibility.
Acquired targets that move inside the radius (CPA) or the time threshold (TCPA)
generate a “CPA/TCPA Alarm” in the message display and the relevant target is
simultaneously assigned a flashing symbol.
The CPA/TCPA zone can be shown or hidden in the radar video as required.