Jerry and all others,

The other post already answered large parts of your post. F16 rules does allow wings in racing as long as you have an equivalent width with regard to righting moment to "more normal" F16's. For recreational sailing or even open class sailing the F16 rules do not aply; here you can do what you want.

So why are wings limited for racing ? we want the boats to be equal and that means that we must draw the line on width somewhere and a equalizing formula. The current F16 class rule 1.2.3. provides this in the best way available.

So why didn't we keep the boat width at 2.5 mtr and allow additional wings reaching beyond the current equivalent width ? Thus keeping road trailing ability and still get more leverage ?

The reasons for that are twofold in general. It is too expensive for the expected return and it adds to the time rigging the boat before sailing.

The last is an important consideration for active racers. Everything adds rigging time, we already need to work out all fittings so they are quick to fix and release for there is alot of stuff on the F16's. Allow additional wings would be an extra item. In beach/water side parking most births are made to accept 2.5 to 2.6 mtr wide cats. Often you will need to take the wings off each time and store them or request (and get assigned) a custom birth.

In addition to this I don't think the builders are hot for it as it adds to the design and this makes the boats more expensive. Builders want simple boats and buyers want inexpensive boats, wings were not regarded to help either. Of course anybody who is willing to pay extra can get any modification implemented. Also wings are relatively heavy for the extra performance they give in strong winds. For example : 1 foot wide wings (30 cm) wings provide the same additional leverage as making the boat halve a foot cm wider in its beam. The additional weight of two (lightweight race) wings of 1 foot extra width will be in the order of 7 kg's at least while a wider beam of halve a foot will add only add about 0.7 kg (= 1/10th the added weight). Even if one made the beams stiffer to compensate for the extra width then the additional weight would be only 2 to 3 kg's.

So from a designers point of view wings are unattractive, especially on a lightweight boat like the F16's, here we just don't have a margin of 7 kg's to put into the wings. It is already a feature to get the boat down to 107 kg all-up weight. Especially with the current stiffness requirement for competitive racing. Designers really don't want to take 7 kg's out of something else and sacrifice stiffness and impact resistance just to have wings. Of course if you are willing to accept the weight penalty and cost penalty than any builder will provide your boat with wings. These things just make it unattractive to market the boat (class) to a large audience.

Maybe this could all be worth it if it would give alot of extra performance. Everything is a trade-off, remember. This however does not seem to be the case. Pretty much in light winds the wings are a disadvantage. For speed you need to lift your luff hull and weight out there makes this harder. Not even looking at aerodynamics. In medium winds the current width is still sufficient so you don't need wings here. In strong winds the seastate plays up and the current batch of F16's are already more limited in all out speed by things like minimum apparent wind angle and rig efficiency than by raw power. On reaches the current width of 2.5 mtr is already on the high side as you can push you bows down when fully powering up. On the downwind legs the current width is sufficient in all conditions. Any more width would only have you sail higher (worse VMG) to keep yourself out. So the only expected gain area is strong winds when going upwind and then mainly when solo sailing. The maximum net increase in speed was calculated as about 4 % on the upwind leg alone, about 2 % overall. A minute gain per hour bouy racing. In other conditions it would not add speed. Of course comfort plays a much smaller role on a race boat so we never included this in the analysis. Also we wanted to F16's to mirror the F18's in as much aspects as possible so racing them first in wins would be fair in teh broadest wind spectrum, Wings (when doublehanding) would only create a difference between the two setups. It was judged that this gain with the linked penalties in cost, weight, rigging time and level performance to F18 was too small to justify stimulating the use of wings in the F16 class rules. We did of course choose to allow them. Wings were not judged to be unwanted, but just unsuited to be actively stimulated in the optimal theoretical F16 boat setup that is underlying the F16 class rules.

Personally I have qualms about sailing under spinnaker in the strong stuff with wings. It is easy for a boat to heel noticeably here. The wings must be raised quite a bit to prevent them from burying. I found that under spinnaker you want the boat to be as simply as possible as you'll need all attention and control to make it work well in rough and strong conditions.

But anyway that was the analyses back then in late 2001. Now we just have to stick with these choices. I for one feel that we made the right choice here.

Of course; for recreational use you are totally free to do what you want just make sure that you can remove the wings (unless they satisfy rule 1.2.3.) before you enter a F16 class race. That is the situation now.

Wouter