Duck footy

Today it was time to finally take out the Duck, a footy designed by G. Sanderson, as far as i know only three hulls were made. There is little data available on the net, but the boat was featured in this article: http://footy.rcsailing.net/articles/my152/footy_design.php
Mr. Sanderson sent me some basic measurments so i could complete the hull, which he sent me almost a year ago, after we met in Sestriere at the 2012 footy gold cup.

The rudder is made like suggested by the photos, her designer sent me, the finn is a 10% chord thicknes helicopter blade

the keel box is 1cm longer than the finn so it's position can be adjusted, the hole in the deck accomodates my 4x8cm servo module, and acts as a hatch

Two balljoints hold the rudder, and a piece of brass tubing secures it with friction

Here is the boat with the karo a rigg

The boat has it's LCB shifted far forward, which makes the waterline round at bow and slim at stern(sort of fish shaped), such volume distribution trimms the boat under heel in a very special way. The stern actualy drops, and the attack angle of the finns icreases with heel and that reduces leeway, succes of such Wl shape was proved this year with Phil Tylers SLiM design.

I didn't do any calculations on this model, so i was unsure of it's balance, but right away it became obvious that upwind balance was bang on!

But nothing is perfect, when nosedivng downwind control was lost at times, because of the rudder which is to short.

Eventually the rigg was changed to the new a rigg with 1500cm2

The CE is recessed some 10mm compared to the original rigg, but that didn't seem to affect the upwind balance.

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Overall i am very pleased with the boat, it seems to be fast in all directions. The wegiht is 360g + rigg(40gmax), which is quite light. Ballast is 200grams.
It will be used for speed and angle comaprison along side with my KAROs for future footy projects.
If interest for footys rises here in Slowenia it will be at the front end of the footy fleet for sure!

Thanks to Mr. Gary Sanderson for giving me the chance to finish one of his hulls!