On-deck the working areas are again both functional and structural. The mono- lithic carbon beams on the foredeck serve several functions: hiding adjustment controls that are kept on-deck so that the deck can remain watertight, acting as foot rails for anyone roaming forward and as structural beams to help reinforce the large panels of the deck structure.
The boards are canted in at a 10° dihedral angle and (for now at least) they are straight rather than curved, to achieve good upwind performance without induc- ing too much offwind drag. They also boast a clever design feature that has elimi- nated the need for carbon posts for their raising and lowering, saving some 150kg each in extra carbon. Using a system that instead features a control line running through a recessed groove in the foil’s side surface, the build team first tank tested this using a large-scale model to make sure the groove in the surface did not produce excessive drag.
Other novel ideas were used in the winch pods in the cockpit, the columnar- shaped structures made of carbon that have to handle those nine-ton sheet loads in shear. Their position leaves just enough room to lay sails on the windward side of the cockpit floor and not impede trim- ming; and structurally these are not anchored just to the deck, but actually protrude straight through the deck and are bonded to the hull itself for maximum structural integrity.
Based on the high-speed hosing the crew
will often get on these boats, Read specified two forward steering stations be added into the forward end of the cockpit so that if conditions were rough the helmsman could be shielded more effectively by the dodger. There are innumerable other details like this, large and small, throughout the boat, showing a level of forethought and carbon craftsmanship that comes only with having previously built a VOR boat (or two or three).
The deck hardware for the manual- driven systems, where as many as 12 strong guys can load up a line, has to be remark- ably strong and efficient. As a consulting engineer on the project, Jon Williams from Stay in Phase worked hard to redesign the winch drivetrain, pedestals, shafts and gear boxes for the Harken system to accommo- date this huge amount of torque, since usually loads this large are handled by power-driven systems with lower torque. And besides being compliant with the requirements of many of the race record rules, by having no powered hydraulic systems there is no need to carry some 1.5 tons of fuel and other equipment necessary to power the engine to drive the pumps needed for a comparable powered system. Other sail-handling systems to note are the soft vang, locks on the reef lines (‘This is a no-brainer for cruising boats too,’ says Read), and a conventional non-rotating boom – Read thinks the rotating variety is suitable only for inshore racing. Although most build programmes have their setbacks along the way, regardless of
experience and planning – this team ran double shifts from August 2013 to March 2014 – Hacket credits having a design engineer from Verdier/VPLP on site for seven months with being able to finish in reasonable time. In all, he says some 120-130,000 man-hours were spent on this project…
So time to go sailing, and Honey reports that the first offshore sail the team did – an 800-mile jaunt from Newport down to Charleston to test their systems, do their qualifier for the Hobart race, and get to the transport ship bound for Sydney – was pleasant, if not uneventful, and a good learning experience. While they missed any strong breeze and lumpy seas in the Gulf Stream that could replicate the Bass Straits, he felt confident that once in Sydney they’ll have ample opportunity to find the conditions they need to prepare for the Hobart itself. Honey also added that their early attempts to start filling out the polar charts were impeded by a broken speed impeller in the bulb: there are also stern-based impellers in the hull, but at high speeds their data is not as reliable due to the violently disturbed flow. But this and other teething pains should not derail progress on one of the most interesting and innovative first-to-finish projects in a long while. Being at the edge of functional manual power and with all her optimisations, it will be interesting to see if Comanche is indeed defining a new limit in what is possible in non-powered offshore monohull design…
SEAHORSE 37
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