take a close look at the pdf, it says area 29204 mm^2 and if I remember correctly that is the total surface area of the bulb.

Choosing the length of the bulb is obviously a trade-off between form-drag, mainly associated with the transverse profile or diameter of the bulb, and surface-drag which depends on the wetted area.

For some reason at IOM Reynolds numbers it seems like thinner and longer bulbs are more popular than on fullsize yachts. If you or someone else can explain this well then I'm all ears!

Thanks for the comments, I try to update as much as I can !

When designing the bulb we followed the golden rule of yacht design: If you don't know what to do - Copy the fast guys !
The NACA 0034-10 profile was conviniently available in the CAD program I use and looked very much like the bulbs on boats known to be fast. Those that know something about these seem to always refer to the low Reynolds numbers at which we operate - making research done with full-sized yachts in mind not so relevant for our scale. Model gliders operate closer to our Reynolds numbers so people have tried to learn IOM fin-design from the glider folks.
If you're serious about doing some homework then a trip to the library, looking up all issues of Seahorse with articles by David Hollom, is recommended. I understand he has designed the SailsETC foils.

For the foil story I was just planning on documenting the fin planforms that seem to be popular today and something about the 85 mm chord 6% NACA fin we've been producing locally.

Anders