Does anyone recognise this weird keel?
I don''t think it is all that weird. I am not a hydraulic engineer and therefore do not know what effect the water flow would have with the two vertical keel members. If you fill it in it would not look much different from the short keel on a friends Catalina 34. Maybe there is something to be gained from the opening? Maybe it is as heavy as the designer wanted, to support the sail plan? It would be fun to see it in the water, maybe hang on to the tiller and see how she feels.To see how she really does, we could sail her against Denr''s Macgregor 26.
I think the design of that keel might be a lot safer than the swing keels the boys are sailing on the Volvo 70s down in the Southern Ocean right now.