Bundles and towed installation

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Bundles and towed installation

TOW CONFIGURATION FOR CDT

Escort vessel

Command and survey vessel

Tow tug

Trail tug

Transponders

Large trailhead

Large towhead

Ballast chains

A typical configuration during controlled-depth towing (CDT) The vessels involved are: Tow tug – typically, this is an anchor-handling vessel, with a bollard pull of up to 200 tonnes and a towing winch with a load monitoring system; Trail tug – typically this requires a smaller anchor-handling vessel, with a bollard pull of about 60 to 100 tonnes and with a towing winch with load monitoring system that is rigged over the bow of the vessel; Escort vessel (warning vessel) – usually, a fishing boat is employed, acting as a warning vessel during transportation of the bundle to the field; Command vessel – usually, this is a DP vessel equipped with ROV facilities, deck crane, deck space for anchor blocks and flooding spread. Survey equipment will include surface positioning package, acoustic positioning package and telemetry links.

SURFACE TOW