Slowed by barnacles
When the Golden Globe Race competitors reached their midway point in Hobart to drop off their camera footage during November, the most surprising pictures were of the growth attached to Uku Randmaa’s yacht One and All.
It soon transpired the Estonian wasn’t the only one who had acquired so many stowaways.
Finn Tapio Lehtinen and Russian Igor Zaretskiy have also suffered huge barnacle growth on their hulls, while Dutchman Mark Slats, currently in 2nd place, said he was “incredibly surprised how many barnacles were attached on the bottom of the boat”.
“I’ve never seen anything this bad in my entire sailing life,” commented race chairman Don Mcintyre when he welcomed the sailors in Hobart. Mcintyre estimates the infestation will be costing the sailors between 0.5-1 knot in boat speed.
His report read: ‘Are these experiences a damning indictment to the ineffectiveness of modern antifouling paints? These boats all had their bottoms painted at the end of May and the coatings have not even lasted six months – and for the last six weeks or so in very cold water.’
Race organisers explained that Uku Randmaa’s Rustler 36 had only two coats of antifouling applied, whereas GGR leader Jean-luc Van
Den Heede had added a third coat as well as a ‘hot’ top coat mixed with copper powder, which erodes. The only barnacles seen on Van Den Heede’s yacht were attached to the gelcoat.
We spoke to antifouling experts at the METS marine equipment show in Amsterdam in November, asking how it is possible for such a build up of barnacles on moving vessels to occur.
Michael Hop, general manager at Seajet Yacht Paints, said that to his knowledge a boat has to be stopped or moving extremely slowly for barnacles to be able to attach to a hull.
Darren Gittins, sales manager for Hempel’s Yacht Coatings, agreed but advised that a barnacle ‘spat’ can happen in minutes. “They could have adhered to a small part between the keel and rudder where there might not have been antifouling,” he explained.
However, Coppercoat’s managing director Ewan
Clarke said barnacles “can and will” attach to moving craft. It would be normal to expect conventional antifoul paint to require renewing after 20,000 miles of sailing, he said.