Quote

... about 1.7m long (about 1.2m below hull), 240mm chord (so aspect ratio of about 5), rectangular planform (easier to make mould). ...



You are building a F16 right ?

Then those boards have FAR to much surface area. You have more surface are then any of the F18's.

All other F16's are between 0.144 and 0.188 sq. mtr surface area per board and you are at 1.2 * 0.240 = 0.288.

As a comparison the F18's have an area per board of 0.200 - 0.255 with the larger area belonging to the older designs.

I expect your boat to feel like it will trip over the boards easily, as the FX-one had as a tendency. These boards were the same size as the Tiger F18 (initially). You have even more then that.

As such I expect you to pull up the boards by 1/3 most of the time ending up at :

Area : 0.192
Depth : 0.8
aspect ratio : 3.33

I have made this prediction before with the nacra I-17's and since a few years their class rules allow the boards to be shortened by 30 % after they too found that singlehanded sailing with too much board area makes the boat feel like it is tripping.

Wouter


Wouter Hijink
Formula 16 NED 243 (one-off; homebuild)
The Netherlands