Furuno 1834C-BB, GD-1920C-BB, 1954C-BB, 1964C-BB, 1944C-BB 26.8 CPA/TCPA alarm ARP, ARP target data

2. RADAR OPERATION

12/LP 3nm

H-UP

Cursor

ARP	01
Target

No.01 VECTOR TRUE 15min

CSE 359.9°T SPD 12.5kt

CPA 2.21nm TCPA 12:35

319.9°T TARGET

A TRAIL

B TLLOUTPUT

C ACQ

D TARGET

INFO

E RETURN

+ 359.9 ˚R 11.70nm

CPA and TCPA

Course and Speed

Target No., Vector Reference (True), Vector Time

ARP target data

2.26.8 CPA/TCPA alarm (ARP)

When the predicted CPA of any target becomes smaller than a preset CPA alarm range or its predicted TCPA less than a preset TCPA alarm limit, an audio alarm sounds and the speaker icon appears (in red). In addition, the target plot symbol of the offending target changes to a triangle and flashes together with its vector. You may silence the audio alarm with the CLEAR key. Press the ALARM key and the message “COLLISION ALARM” appears. Press the C: CLEAR ALARM soft key to acknowledge the alarm. The flashing of the triangle plot symbol continues until you intentionally terminate tracking of the target. The ARP continuously monitors the predicted range at the Closest Point of Approach (CPA) and predicted time to CPA (TCPA) of each track to own ship.

This feature helps alert you to targets which may be on a collision course with own ship. However, it is important that gain, A/C SEA, A/C RAIN and other radar controls are properly adjusted and the ARP is set up so that it can track targets effectively.

CPA/TCPA alarm ranges must be set up properly taking into consideration the size, tonnage, speed, turning performance and other characteristics of own ship.

CAUTION

The CPA/TCPA alarm should never be relied upon as the sole means for detect- ing the risk of collision. The navigator is not relieved of the responsibility to keep visual lookout for avoiding collisions, whether or not the radar or other plotting aid is in use.

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