Does anyone recognise this weird keel?
Sasha, you can read up on this keel development by visiting the Etap site, altho'' the keel you photographed is not an Etap as it has a broader wing than they use (as I recall, at least). There was a new brand intro''d at the London Boat Show in 2005 that featured a keel very much like this but I don''t think that brand will have circulated down to Tasmania so soon. No doubt, the keel design was applied to an earlier boat design which is what you are seeing...unless it''s an Etap.
It does raise a number of questions but it also provides some measurable performance improvements over a conventional keel. And of course, departures from anything conventional on a boat always invite lots of criticism (often in the absence of data, I might add). Perhaps it would look more ''normal'' if we viewed it in the geographic context in which it evolved: these designs come from a segment of N Europe where there is much shallow water and yet where the sailing can be spirited in winds off the North Sea. Etap (Belgium-built) is trying to appeal to a sailor who wants good performance out in the Frisian Is. or in the Dutch ''Schelde'' estuaries that have been dyked over, as well as in other waters like the Chesapeake Bay, W Florida and perhaps the Bahamas. This is just a different approach to try and minimize leeway, support ample sail area, and provide good stability, odd tho'' it might appear.