(IIRC i ised area .223 and depth 1m (just to get 4.5 aspect ratio)) If you re-read my post I said I used max plate ratio as people were arguing about actual plate sizes
Yes, but since then people have intepreted your rating numbers as being for the standard Taipan 4.9; of which they have a feel for actually performance. Either way, a larger misunderstanding is perpetuated.
Also
Is a rediculous set of specs for Taipan or F16 boards. It will make the boat bad behaved and mostly likely significantly slower in all conditions as the board will not be operating at the optimal angle of attack. (best lift to drag ratio).
from very earlier onwards (I think a year after the design waslaunched) the Taipan boards were made narrower and maybe also shorter. Since then the board area (per board) = 0.290 * 0.55 = 0.1595 and the wetted depth is 0.550 mtr. This has not changed since then. The max specs given in the Taipan class rules are useless as no-one is even getting close to those. If more then 10 boats out of 325 build still sail with the old original daggerboards then I would be surprised.
Also 1 mtr long boards (as in wetted length) are unrealistic For Taipan's and F16's. For reasons of optimal lift to drag ratios you'll need a minimal angle of attack and this requirement limits the boards area for these boats to 0.185 sq. mtr. or less (preferably slightly less). In order for such a board to be 1 mtr long it needs to be 185 mm wide or less. This is too little to make the board both strong and stiff enough. So this board can not be build in an economic viable way. Of course, a custom board can but you'll be pouring that full of carbon cloth to get at the required specs.
Commercial builders however won't take these risks for their production boats, especially not when such boards are not really attractive because of the ease of stalling them or "tripping" over them. Both well proven disadvantages of very long/high aspect boards.
So up till now all builders are converging on F16 boards that are around 0.75 mtr long and on average just under 0.200 mtr wide. Resulting in rougly 0.150 sq.mtr. area and averaged aspect ratio's of 4.
I think your own boards, Simon, are the only exception to this rule at this time.
Wouter
