One of the noticeable developments in the evolution of the catamaran CTV (Crew Transfer Vessel) was the increase in engine power and hence the physical size of the engines installed. Initially, at the dawn of the offshore windpower in the UK (2005), the first fast cat CTVs were powered with twin diesels of around 400 BHP (280kW) each but by 2011 they were squeezing twin 1300 BHP (910kW) units into the slim and arguably flimsy aluminium hulls.
It’s worth noting that the majority of CTVs from the smallest to those up to 28 metres in length and regardless of installed horse-power, are limited to 12 passengers by UK regulation (unless the CTV is run as a non-‘small vessel code’ ship). The available deadweight for cargo carrying capacity is bigger in the larger vessels however.
These larger engines, when installed into slender catamaran hulls, only just fitted in the space available. There was often very little room on either side of each engine to allow visual inspection or access of any kind. This did not encourage ready physical monitoring (as opposed to instrumentation) by the vessel crews in the same way that readily accessible plant would. It made maintenance and filter changing a bit of a nightmare in some vessels. The result was often that ‘silly’ things like a loose filler caps or blocked vent pipes went un-noticed resulting in a total shut down of the main plant at the most in-opportune time.
The following photos will attempt to demonstrate just how ‘tight’ these CTV machinery spaces have become. They were all taken by allatsea during the construction phases of the London Array windfarm (175 turbines) and Thanet windfarm (100 turbines).