For those who dont know, this accident was on the return delivery following the Sydney Hobart
From Sailing Anarchy - https://sailinganarc...son-ker-speaks/
I’d like to make clear that the keel lost by the Ker 40 ‘Showtime’ was not designed by Ker Yacht Design. The yacht had a retrofit keel fitted, designed by its owner’s local design office near Sydney and built by a local fabricator.
We have designed a great many keels over the last 23 years which have been constructed by many different builders around the world, none have ever failed. To the best of our knowledge, Showtime is the only yacht designed by us to have had a keel fitted that was not designed by us.
The keel, designed by the owner’s local Naval Architect, was configured as a vertical hollow strut welded to a horizontal mounting plate, which in turn was sitting in a shallow recess in the boat’s hull and bolted to the boat’s structure. This is not a design approach we would ever endorse as the high stress point at the junction is coincident with the horizontal welded joint.
The skipper of the delivery voyage Rob Buchanan and his crew only survived through extremely calm thinking and bravery under stressful circumstances. Rob woke hearing a metallic ‘Ping’ just before he was thrown across the boat from his windward bunk as they capsized.
While they made their plans to escape it was apparent to Rob that the inverted boat was holding air pressure in the hull, so the top plate of the keel can only have remained fully bolted to the yacht. When the crew swam down out of the boat, they saw that the vertical part of the keel was missing, revealing that the keel had failed at the welded joint between the exposed vertical and the recessed horizontal parts.
Ker Design would support any World Sailing move to ban this low cost but high risk style of ‘welded T’ keel construction.
Great Article Jason, and I completely agree with your comments on this design.