Aluminium Marine Consultants (AMC) has developed and so far delivered four new catamaran crew transfer vessels (CTVs) specifically suited to offshore wind turbine installation and maintenance.
With the number of offshore wind farms set to grow radically, AMC has developed the Category 1, Bureau Veritas-classed catamaran CTV in conjunction with an offshore wind farm contractor, who ordered four. The fourth was recently delivered.
CTV Design
Named Tempest, Tornado, Typhoon TOW and Hurricane TOW, the first two are 23 m long, the latter pair 25 m. All have been engineered to be essentially similar, allowing interchangeable crewing. The CTVs meet both current and future standards and guidance. The forward and aft deck areas each have space for 10 tonnes of cargo and a crane can be mounted if needed.
The vessels can achieve 28 knots, but also offer good seakeeping qualities and the ability to remain at sea for extended periods. The semi-displacement catamaran hull and 1.4 m draught, coupled with a high waterline, give plenty of room for waves to pass between the hulls, thus preventing slamming. This also translates into more space in the engine compartments, giving easier maintenance access, and comfort for the twelve passengers and three crew.
CTV Propulsion
The 25 m CTVs have a pair of MTU 12 V 2000 M72 twelve-cylinder engines (1080 kW each). The 23 m vessels have 10 V engines. They drive Rolls-Royce Kamewa A3 56 water jets fitted with a compact, reversing bucket able to deliver as much as seventy per cent of the normal forward thrust, together with a ten per cent higher bollard push. The latter not only helps transit efficiency, but keeps the vessel pushed onto turbine towers in high seas.
Monitoring from Shore
MTU’s Blue Vision high-speed internet connection allows the propulsion system to be monitored both aboard and ashore. Engine data can be evaluated to allow either operation or fuel consumption to be tweaked to give the most efficient performance for prevailing conditions.
While primarily intended as wind farm support vessels, the CTVs can also be deployed for dive, survey, and ROV operations.
Picture: AMC’s Hurricane TOW during sea trials.
