eastcoastdude

i expect the reason it has not been raised is that so few people attended the regatta in question, very few people have experienced it.  I guess the organisers asked for (and I hope have got) direct feedback rather than asking competitors to post it on tinternet.  Does seem a little odd, however.  The premise that the solution to a lottery is a new lottery is a little crazy.  I remember someone telling me that the proposal for the mens 100m in Rio is that they run the heats etc in the stadium and the final in the street or on the beach.

The issue with sailing a T-foil when the boat is heeled is interesting

Whilst vertically set the vertical steers and the horizontal foil provides lift. Add a little bit of heel and it all gets a little bit confusing as to what is steering and what is providing lift. Helmsman has to guess! Airplanes have lifting foils and steering foils. They keep it separate as they don't like crashing as much as we do in dinghies. Yachts don't like crashing either.

There are some very good points about why Stamm's DSQ should be upheld.  

However, I was not there, and apart from a single Russian I don't think anyone else was.  There is clear precedent with Mike Plant and the NoR is definitive about a material breach.

What I don't understand is that at the start of the race 4 years ago Pindar still had support team on board after the designated cut off time for all boats to be solo.  Pindar was receiving outside assistance.  If I recall correctly there were some electrics issues as the boat was late and not properly prepped.

Pindar received a time penalty after a protest which was made to the IJ and upheld.  Clearly a different Notice of Race last time, a different IJ and I am also unable to find anything on the web about either the protest of the 2008 NoR.  However that sanction seemed appropriate then and a similar sanction feels appropriate here.

Just saying.

I am currently working on "t" foils with Mark Thorpe (for A Class Cats) and as part of this, we have revisited some of the work done on Moths, which I believe was one of the first classes to use T's (well before the 14's). While there was a Moth wing a T foil back in the 60's, they came to be used on narrow lowriders in the 1990's. With that hull form, they were used soley for pitch control and were set pretty much to neutral. Mark did a lot of testing and found no benefit from increased lift - in fact, the drag made it slower. The real benefit was the reduction in pitching upwind, coupled with the ability to drive the boat a lot harder downwind. We also believe that the endplate effect of teh T meant more rudder control and/or a smaller rudder.

I took these ideas and was the first person to use a T foil on a National 12. Again, I added this to the bottom of the rudder and it was set a pretty much neutral. Again, the benefits were reduced pitching and being able to drive the boat harder downwind. I tried changing the amount of lift but it always slowed thge boat down.

I think what this showed me is that to gain benefits from lift from a T foil, you need to design the whole boat around it. There are benefits from just adding a T because of pitching etc., but to get the reduced displacement, recovered enefrgy and any other such benefit, it has toi be a bit more than simply bolting on a T. For isnatnce, in the 14's, it is clear that you need a gantry to get the foil in the right place, and the Beiker hull designs optimised for T foils are rather different from those that pre-date T's.

I was initially surprised that Julian suggests that t-foils don't work on some boats, as my experience is that they do benefit every boat I have tried them on or seen them used. However, I can see that if a boat doesn't have nosediving tendencies, maybe pitching control upwind isn't enough to overcome any drag penalty. What i do believe is that you cannot get all the benefits discussed in every situation.

Does the foil actually have to be attached to the rudder? Can it be attached to the stern with aero struts that can be raised above the surface when the benefits of the foil are not needed or the drag of the foil exceeds the benefit.

Foils need to comply with class rules and the normal one which causes problems is the maximum length rule.

I have seen some boats which have systems which allow the foils to be raised by either having a daggerboard style rudder in a cassette for example. This relies on the rudder blade being capable of being substantially smaller when foils are not required. Actually it is surprising at how low speeds that the lift appears to outweigh the drag.

National 12s are unique compared to other boats I have come across in that foils are working at much lower speed than in other classes. Sections being used are similar to those in 14s although successful foil arrangements tend to be swept dihedral rather than cruciform