T foil rudders on Cherubs?

   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.

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I luv Wight Send Private Message Find Member's Posts Visit Member's Homepage Really should get out more Joined: 28 Jan 05 Location: United Kingdom Online Status: Offline Posts: 628	Post Options Post Reply Quote I luv Wight Report Post Quote Reply Topic: T foil rudders on Cherubs? Posted: 28 Dec 05 at 9:24pm
	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.

Chris Noble Send Private Message Find Member's Posts Really should get out more Joined: 26 Nov 04 Location: Scotland Online Status: Offline Posts: 710	Post Options Post Reply Quote Chris Noble Report Post Quote Reply Posted: 28 Dec 05 at 7:28pm
	there are many benifits to them but only more so when planing, from all the info ive had on them they are not benificial in non planing conditions but make the biggest difference in marginal on off planing conditions apparently. I shant go into a schpeel about all the other stuff though unless someone wants my tupence
	Competitive Boat Insurance From Noble Marine FOR SALE: I14 2 Masts 2 poles 3 Booms, Foils Kites/Mains/Jibs too many to list.

Wave Rider Send Private Message Find Member's Posts Visit Member's Homepage Really should get out more Joined: 27 Oct 04 Location: United Kingdom Online Status: Offline Posts: 909	Post Options Post Reply Quote Wave Rider Report Post Quote Reply Posted: 28 Dec 05 at 9:31am
	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?!
	-[Franko]- Chew Valley Lake Sailing Club RS600 933

Isis Send Private Message Find Member's Posts Visit Member's Homepage Really should get out more Joined: 01 Sep 05 Online Status: Offline Posts: 2753	Post Options Post Reply Quote Isis Report Post Quote Reply Posted: 27 Dec 05 at 11:42pm
	yes. is the short answer there are probibly only about 4-5 boats with them fitted but they are worth having (on the newer designs at least) from what ive heard

Guest Send Private Message Find Member's Posts Newbie Joined: 21 May 04 Location: United Kingdom Online Status: Offline Posts: 0	Post Options Post Reply Quote Guest Report Post Quote Reply Posted: 27 Dec 05 at 11:10pm
	Seems they have transformed the 14, do the Cherubs use them? Rick