We reckon The Cone of Silence is about as bitchin as you can make a 30'. A few of you had some follow up questions from the recent feature we did on the boat, and owner James Neill doesn't have enough to do getting ready to take the little rocket to Hawaii, so he filled in some of the blanks. Enjoy.

Keel

The keel is deep but a tiny profile. It has a pretty normal looking torpedo bulb. When you look at it, the keel seems ridiculously thin to be attached to so much weight in the bulb but it is solid carbon. It weighs about 80kgs. I couldn't tell you the bulb weight without getting Jim Pugh's OK.

The fin was a real pain in the arse to build. It has roughly 90 layers of carbon and required over 25 separate oven 'cooks'.

The top of fin attaches to a much larger rectangular section which goes inside the boat and wedges into something similar to standard centerboard case. The centerboard case runs from the floor to a height of about 2 ft high and the keel is locked down onto it with a sealed stainless steel plate. You can remove the plate and lift the keel up through the hatch way to give a draft of less about 2 feet for transporting. When we lift it out we lift it by the keel - i.e. we attach the crane to the keel, lift the keel up, which then pulls on a strap attached to the boat and lifts the boat.

Canting Keel

I can't say that I know what a canting keel boat would be like so its tough to determine whether the 'skiff' configuration Jim Pugh and his team went with for The Cone of Silence is better for a little boat then a canting keel.

The way I understand it, the advantage of canting keel is lower weight for the same or better righting moment. The advantage of better righting moment obviously is simply that you can carry more sail. Wild Oats, which has a canting keel with CBTF sails out of the same Club as The Cone of Silence. Wild Oats does get great height upwind so maybe CBTF has a bit of an advantage there but it seems it would weigh quite a bit more in a 30 footer which would soak up the gains.

If you look at it, I think Jim Pugh seems right in that it seems that the 'skiff' configuration is likely to deliver a lower 'crew plus boat weight' than a canting boat in a light 30 footer.

Obviously big canting boats get lower weight by reducing bulb and reducing crew. For small boats: two factors are relevant:

1. Offshore rules for stability - if you look at the weight of our keel, we couldn't make the bulb significantly lighter and still meet the stability rules so canting is not going to reduce bulb weight much
2. Crew weight - we need 5 or 6 guys to sail the boat effectively. On windward leewards, we actually sail with two or three more than that to get bit more righting moment upwind and on long races we generally sail with 6 or 7 but have to also have to more carry food and water - all up this adds say 200kgs of weight to a 'canting keel' crew of 5. It seems that when you count up batteries, gen sets, the mechanism itself, etc etc canting keel costs about 400kgs.

The other side of the coin is "Could The Cone of Silence usefully use more sail area?" i.e. could it use more power if the canting keel delivered more righting moment. The flippant answer is "Of course !!" because no one says 'no' to more power. The reality is however that it would not make a lot of difference except perhaps close reaching where Wild Oats seems particularly quick.

Off the wind - the reality is that we are probably hitting the limit of efficiency already as The Cone has a quite a lot of sail area already. The reason for going bigger would be to develop more power to get onto the plane earlier but bigger would mean bigger mast and heavier deck hardware plus the weight of the canting gear which would make the boat heavier and therefore needing more power to get onto the plane. Once planning, I suspect that speed is more a factor of efficiency and drag than using 'a bigger engine' - both sail drag and underwater drag so I doubt that bigger sails would make a lot of difference.

Upwind, canting keel might give a bit more but I think a number of modern 30 footers are getting toward the point where there are only get small increments of improvement left to get and we are not going to get a big jump in VMG. We simply don't get much advantage from 200kgs more on the rail when we use it in windward leeward races and beyond that we don't seem to get anything. I don't know enough about CBTF to know whether it makes a big difference and whether for example that could be picked up with a trim tab. I guess you lose a bit canting the keel during tacks.

Spreaders not full width - two reasons:

1. They are wide enough - wider added drag without significantly increased geometric efficiency
2. There is enough gap for us to sheet our overlapping headsails inside the lifelines - i.e. our code 0. It helps for light upwind.

Spreaders - 22 degrees

Cost - well I think I'll take the 5th on that one!

Moulds

The molds are owned by Brenmark - they are female moulds, for low build cost and low weight boat with minimal hull fairing. Phone 61 7 3274-5751

All sails for Transpac are by Quantum except for the spares

Headsails

• 1,2,3,4, storm jib 25 - 5 sq M
• Jib top 35 Sq m
• Code 0 45 sqm

Spinnakers all asymmetric

• Code 2 masthead Runner 185 sq M
• Code 3 masthead Reacher 145 sq M
• Code 5 Fractional Reacher 110 sq M
• Code 7 Storm Reacher 75 Sq M
• Spares Code 2,3,5

Mainsail 42 Sq M

Propulsion

You really have to see it to understand it - it is simple when you see it but difficult to describe.

In essence the drive unit which sits recessed about 10 inches into the hull just behind the keel There are two trap doors - one in front and one behind. You open the trap doors (upwards) and the water gets sucked up through front trap door to the drive unit and shot out the back trap door to drive the boat. The drive unit is a modified Tohatsu outboard motor.

The Pole System

The pole is about 16ft long of which about 12 ft sticks out the front of the boat. It rotates through 40 degrees - when fully rotated the pole end is about 1 foot wider than the beam of the boat. In theory they say you should not use all the rotation but in practice we use it all most of the time when VMG running above about 5 knots of true breeze.

The stem fitting to which the forestay is connected is in essence a carbon hoop between the deck and the forestay. The pole goes through that hoop which acts as the fulcrum point - no bearings. The back of the pole is attached to a radiused mainsheet traveler type track which travels through about 3 ft onto 'horns' which hang about 6 inches over each side of the bow. All the control gear is on the deck - a bit messy to look at but leak proof.


Regards,

James Neill