A rightly proud Jo Richards introduces Eeyore to her public. Take an unlamented 3kt sh*tbox (to use a favourite Sailing Anarchy technical term), add some typically inspired Richards free thinking, plus a ton of elbow grease and a lot of scavenging in some very high-class places, and you have a beautifully finished pocket cruiser capable of winning one of the biggest yacht races in the world
replaced them with a fin keel I had sitting around (the bulb I cut off the keel ended up on Ziggy – which finished second behind Eeyore in the Round the Island Race). But it was always the plan to go back to bilge keels after I’d given it some thought. My view was that nobody has seriously
looked at bilge keels in the past 40 years – why would you! I enjoy looking at the logic trail and seeing where it takes you. It appeared that the major problem with the old low-aspect bilge keels is that the lead- ing edge is so far forward in the boat that it is operating in the water flow that is still going outward around the hull. This changes the angle of attack on the foils, effectively giving you toe-out. The effect is the opposite of snow-ploughing on skis, but it leads to the same effect. The only way to deal with this is to
move the keel root aft, but to make the boat balance a negative sweep back on the leading edge is now needed to get enough keel area forward. I also remembered as a child that there
was a lot of ‘galloshing’ of air trapped under the windward keel. To prevent this I short- ened the keel root as much as possible which also helps keep the centre of gravity low. Structurally cast iron was the sensible
option. The keels also flair out at the root to provide a wider footprint on the hull. They are symmetrical except that the filler
46 SEAHORSE
radius to the hull twists slightly inboard at the leading edge to match the flow across the hull.
Pinning the tail on the donkey The fore and aft position of the keel is dictated by balance considerations. Having sailed the boat with a fin keel for a couple of years I essentially replicated the centres of area. I chose to ignore the potential slight yaw imbalance caused by the leeward keel working harder than the weather one. Obviously the closer the keels are to the
centreline the more parallel they are to the flow over the hull. I was, however, worried about the ‘blockage’ effects between the keels. To help this the keels cant outward at 16°, a reasonable upwind heel angle allowing one keel to be upright most of the time. The windward keel now at 32° is about the same as a heeled (single fin)
‘Oh, Eeyore, you are wet!’ said Piglet, feeling him. Eeyore shook himself, and asked somebody to explain to Piglet what happened when you had been inside a river for quite a long time AA Milne
Version 5 America’s Cup boat – so hope- fully still contributing side force. Just after I’d bolted the keels on Gio-
vanni Belgrano came into the workshop. His view was that the blockage would be minimal and that I could have put the keels closer to the centreline. However, upon sailing we found that if they were any further inboard it would have been impos- sible to see or remove weed from the keel root – you have to be lucky sometimes. Performance has been everything I
could have hoped for. We can hold a lane upwind and there are no vices whatsoever. The Alacrity’s fat bowed hull form
works a little like some of the modern Mini Transat boats, making maximum use of limited overall length. One point of interest is that with the bilge keels we are definitely quicker with a fatter rudder section than is the norm nowadays. Luckily the project coincided with the
IRC rating office increasing the penalty on draft, and as a result benefiting Eeyore’s new-found lack of draft (only 900mm in our case). That together with the change in hull factor has allowed us to optimise other areas of the boat so we have a competitive all-round performance. I look forward to a beer on the beach
with some other ‘racing’ bilge keelers soon! Jo Richards, Gurnard, Isle of Wight q
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