What causes CPA alarms on ARPA?

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Multiple Choice

What causes CPA alarms on ARPA?

CPA alarms are about potential collision risk. ARPA continually calculates the predicted Closest Point of Approach with each target and the Time to CPA. An alarm is triggered when the predicted closest separation is smaller than the preset CPA limit and/or the time to that point falls within the preset warning time. In practical terms, if a target would come closer than the defined safety distance and that moment would occur within the warning window, the system alerts you. This reaction is specific to predicted closeness and timing, not simply because there is no risk, a vessel is stopped, or there are many targets.

CPA alarms are about potential collision risk. ARPA continually calculates the predicted Closest Point of Approach with each target and the Time to CPA. An alarm is triggered when the predicted closest separation is smaller than the preset CPA limit and/or the time to that point falls within the preset warning time. In practical terms, if a target would come closer than the defined safety distance and that moment would occur within the warning window, the system alerts you. This reaction is specific to predicted closeness and timing, not simply because there is no risk, a vessel is stopped, or there are many targets.

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