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Patrol Vessel Vigilant

Picture of the Vigilant

The MV Vigilant is an ex-South Australian police boat which is contracted and managed by International Networks and Technology on behalf of the submarine cable owners to patrol the cable approaches to Sydney to minimise the risk of damage by bottom-trawling fishing vessels and by anchoring ships.

The patrol vessel is equipped with state of the art radar, differential GPS, video camera, still cameras, gyro-stabilised binoculars and computerised navigation system to assist in locating, tracking and identifying vessels which may be a threat to cable security.

Fishing trawlers tow heavy trawl "doors" or "otter boards" attached to sweeps which hold the trawl net mouth open. These heavy doors are towed along the seabed and can slice through the cable insulation causing a shunt fault (where the power in the cable is shunted to the sea i.e., to earth) or they can severely kink the cable which disrupts fibre optic cables by causing high transmission losses.

A typical patrol day commences at 3am when the crew prepare for departure. The average length of the patrol day is 15 hours and requires the vessel to patrol the cable route looking for ships which may be anchoring in or near the prohibited anchorage zones which protect the cable near the shore approaches, and to look for trawlers which may trawl across the cables.

The purpose of the patrol boat is to educate the fishermen as to the location of the cables, not to stop them fishing. This education includes the handing out of cable coordinates data and navigation chartlets showing the location of the cables. The patrol boat has been very successful in protecting Telstra's cables from damage caused by commercial fishing activities.

Name MV Vigilant
Built 1984
Baseport Sydney
Owner/Operator Ace Boat Charters
Purpose Cable patrol
Engines 2 x 485 HP Turbo-charged Detroit Diesels
Speed Cruising speed - 18 knots
Maximum Speed - 22 knots
Length 17 metres
Beam 4.4 metres
Crew 2

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Last Modified: 19-09-2000
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