Fast cat can morph into liftboat

Invented by Dennis Knox of OSSeas Consulting, Tortola, British Virgin Islands, the SHC Wavedancer is a concept for a submersible hull catamaran.

It is described as "essentially a high speed catamaran similar to large ferries of that class" that can transit to and from a site at around 50 knots (90 Km/h) and once on site can transform by jacking the superstructure up on vertical struts and ballasting down the two hulls.

This moves the superstructure up above the wave tops and the hulls below the wave energy zone, resulting in a very stable work platform in sea conditions other vessel would find unworkable.

Among possible applications seen for the submersible hull catamaran are:

• Maintenance of wind farms in 90 percent of weather conditions.
• Full field platform crew changes (dispense with helicopters).
• Cable laying - work in 90 percent of the weather.
• Hydrographic and geophysical surveys, slow speed stability.
• General platform resupply.
• Small diameter reel pipelay in 90 percent of weather conditions.
• Placement of light lifts on the seabed.
• Installation of wave or tidal arrays.
• Emergency access to stricken vessels in rough weather.
• Rapid response for oil spill containment.
• Scientific research.
• Installation and servicing of telecommunications cables.
• Drill rig support and drill pipe carriers.
• Accommodation vessels for hook up and commissioning.
• Seismic surveys.
• Oceanographic research and equipment deployment / recovery.
• ROV inspections services.