Operation Manual

User Manual

• Transmit details of their own vessel

• Receive details from other vessels or navigation aids within VHF range.

Information being transmitted from vessels over 300 tons that, due to recent world-

wide legislation, are required to fit Class “A” AIS transponders.

Connecting to the chart plotter an AIS receiver (please contact your local dealer),

vessels with AIS transponder within VHF range are displayed on screen giving the skipper

or navigator a visual interpretation of the data of nearby vessels. This improves safety, and

specifically for collision avoidance reasons.

5.7.1 AIS SYSTEM DEFINITIONS

• Target

It is a vessel equipped with AIS. Information about the targets is being received by

AIS Receiver and displayed on the screen.

• CPA

Closest Point of Approach is the closest distance that will be achieved between your

vessel and the tracked target, based on your vessel’s speed and direction and the

target’s speed and direction.

• CPA Limit

This is the distance from your vessel that a target may reach before a target is deemed

a threat.

• CPA Alarm

Occurs if CPA is less or equal to CPA Limit. This test is done for active targets only.

• TCPA

Time to closest Point of Approach is the time remaining until the CPA will occur.

• TCPA Limit

This is the time remaining before the CPA is reached.

• TCPA Alarm

Occurs if TCPA is less or equal to TCPA Limit. This test is done for active targets

only and if CPA value is less or equal to CPA Limit.

• Radio Call Sign

International call sign assigned to vessel, often used on voice radio.

• Name

Name of ship, 20 characters.

• MMSI

Maritime Mobile Service Identity.

• MMSI number

A unique 9 digit number that is assigned to a DSC radio station. It primarily regis-

ters the boat information in the U.S. Coast Guard’s national distress database for

use in emergency situations.