In an update to last year’s Momentum article on the project, two fast ferries destined for Mexico’s largest ferry operator, Ultramar, have been launched at Wight Shipyard Co’s Isle of Wight facility.
Designed by Incat Crowther, both the 37-metre ferries feature fully CFD-optimised propellers, with a diameter in excess of 1.2 metres, and are amongst the first commercial vessels of their type to benefit from flow-aligned rudders, which reduces rudder resistance by being adapted to the propulsion systems lift, drag and torque. Through their innovative design, which is perfectly aligned with the ferries’ propeller flow angles, premature cavitation and vibration are reduced by lowering the suction pressure peak that can form on or near the leading edge of the rudder.
James Day, Naval Architect for Wight Shipyard, commented on the project and the experience of working with CJR’s team: “We know that by working with CJR, the end result is going to perform exactly as we expect and, with reputations on the line, that peace of mind means a great deal to us and our customer. Cancun (Mexico) has few ship maintenance facilities, so a poor performing propulsion system would not only cost more money to operate day to day but could mean the boats are out of the water more often and for longer. CJR’s scientifically-driven approach to design and manufacture reduces the risk of vibration and premature cavitation, so the ferries will operate for longer without issue. Also, the fuel efficiency and performance benefits that CFD design and CNC manufacture provide are now well understood. On commercial vessels that are in operation all day, every day, that optimisation adds up to very real cost savings.
Beyond the delivered product, boatbuilders also need to know that the experience of working with a propulsion specialist is going to be a collaborative and pleasant experience. And that was precisely the case, as Ollie Gove, Engineering Manager for Wight Shipyard explains: “From initial contact to delivery and install, CJR’s team are just easy to work with. We expect a quality product, but it still needs to work from a financial perspective – we can’t go back to a client and tell them the price has changed simply because a partner misunderstood or miscalculated the complexity. Thankfully, through open communication, asking the right questions, and CJR’s experience of this type of project, there were no issues on these fronts.”