…Published in June 2007 issue of Yachting World

Problems with Rondal’s Hydrofurl headsail furlers that have seen them release reefed sails under load have been put down to an inadequate locking pawl and undersized sprocket in the gear with which the pawl should engage.

Incidents aboard the 55m (180ft) Adèle that caused damage to the sprockets and the pawl led Rondal to redesign the units. Remco Zeevaarder of Rondal says the furlers have a hydraulic disc brake which engages when furling is complete. This releases at a certain level of torque on the unit – in a rising wind, say – whereupon a pawl should engage with two of six sprockets on a gear fixed to the furler.

Rondal found that the pawl with which the sprockets should engage was too small and sometimes out of alignment, and that the sprockets were also too small. Larger sprockets and pawl have solved the problem, say Rondal.