F16 Optimization – The Mainsail

In the last post of optimization I talked about the jib.  Let’s see now the main motor, the mainsail.
Everything has started with this sail modification. A team from France asked me to make a more powerful sail for the Europeans. I was thinking a lot which direction to take as I was pretty happy with our first mainsail design. It had a 6 batten.

As our F18 mainsail is pretty successful I chose to use the 7 batten layout. The first 7 batten set was made for the Europeans to Cesenatico. It was a little bit too much on the power side, as needed to use too much cunningham as the wind picked up a little.
This set made the 2nd place at the Europeans
Basically the batten layout changed a lot during some months and generations.
Evolution of the batten layout
After the Europeans we continued the optimization. I started to use our F18 shape too, with different luff curves for different conditions and crew weights. For hobby sailors or for ones who changing a lot the crew, I found the AP luff curve which is in the middle. The #85 got the one, which is really good in shape wise and handling and batten layout is the one I like too. I gave a slightly bigger head to this design.
The #85 mainsail
After this set we introduced the 1D membrane. It is light, stiff, but long lasting material. The first sets were the pinky ones, one went to France and one to Oman. They were really the same shape as the #85.
 The winter came and new ideas appeared. For the next generation, for the 2k16 mainsail I have modified the angle of the head for better flow and making some cut-down too for using more space on the mast. So the final cut was the FRA5, which was on the Paris Boatshow. Manu and Théo used it on the Martinique Cata Race with a great result and the sails, showed their power and speed.
2k16 mainsail
For sure, There are some ideas in my mind what to change, and how to speed up more the guys for the F16 Worlds. 
I haven’t talked about the battens. i am on favor to use the ideal batten sets for different conditions. It worths a separate post.