T foil rudders on Cherubs?

Seems they have transformed the 14, do the Cherubs use them?

Rick

Yep, i've heard they make a massive diffrence on boats which have them and are down to weight. I think in non planing conditions they are a big help too?!

The benefits appear to be less pitching upwind ( especially in light winds and a bit of slop ), and more stability fore and aft - which is not always a good thing.
The major advantage is trapezing upwind in f3+ with both crew well aft, supported by the T-foil lift. There is less drag from the hull due to lower displacement, and this reduction exceeds the extra drag from the T-foil.

The boat is now not very sensitive to crew position trim, the T-foil controls the trim angle. The lift varies hugely with boat speed ( proportional to square of the speed ), and so continuous angle adjustment is required.
Some boats use foils fixed to the blade, adjustment by raking pivot pin, with string/cleat adjustment.

Alternatives are adjustable angle foils, controlled by twisting tiller extensions.





twin extensions rotate shaft attached to drum attached to cable attached to crank attached to long push rod inside blade attached to lever arm attached to shaft attached to foil blades . - simple really !

This setup enables the blade to be fully retracted for launching etc.

The narrow P7 has less of a pitchpole issue than the blunt-bowed bistro type. The narrow entry angle, carried right up to gunwale level means that it pierces the waves, without much slowing down. You can dip the bow, and still sail fast, and wait for the bow to pop up again.
I havn't done a real pitchpole in my P7 ( but i do know a man who can pitchpole his in a f3! ) It seems to help if the crew stays back if the nose dips, instead of running forward up the gunwales, and then flying round the front.

The upwind lift should benefit the wider hulls too.

& oh, Aquas & Primals foils are very easy to make - fixed "T" on the rudder blade and just knock the rudder stock back and forth! No little fiddly bits to go wrong, sorry Andy, not aimed at you, but if I tried making yours Id prob Fek it up!!!