Big IOR sailing yachts (60 feet+) have relatively large head sails and a smaller main sail. Furling the head sails, for reefing or for storage, cannot be done manually due to the enormous areas and high forces on the sails. Furlers on big boats are seriously powered, either by electro motors or hydraulic systems.
The downside of a furler is that it needs space. In modern racers, with almost vertical bows, there is enough room to bring the furler down the deck. But on older IOR racers, the bow section is so sharp that there is no room at all down the deck. The furler needs to be placed above the deck, taking away some important square meters from the head sail.
Gijs van Liebergen, owner of the King’s Legend, got the idea to separate the drive unit from the furling unit and asked Maurits Homan industrial design engineering to work this out to a concept and later to a final product. The much smaller furler could be placed on the fore stay just above deck level, and the motor could go aft, down the deck. To connect the units, an endless loop of 10mm high-tech kevlar cord is used. The sail could now remain the full size.
Simplified test models were made to determine holding power, friction and wear. A prototype is installed on the King’s Legend, a legendary Swan 65(*), and is tested now in the worst conditions possible: 24/7 continuous spray of salt water, direct sun light and extremely heavy loads.
Some numbers:
- Axial load 30,000 Newtons
- Radial load 15,000 Newtons
- Motor power 650 Watts
- Material: Stainless Steel AISI 316 and 316L
(*) The King’s Legend sailed the 1977 Whitbread Around The World race, a race of more than 27000 nautical miles. She came in as 2nd, behind the Dutch winner, the ‘Flyer’. Today, King’s Legend sails regattas, cruises and company events. More information about the King’s Legend: www.kingslegend.com
