Hi all. "T" foil rudders are GREAT ! Dont know if you know but the Stealth has a "cartridge" style of rudder where it just slides up and down in its stock. Okay you have to pre-fit the rudders from the bottom up but the a shock cord holds them no problem. As for launching and retrieval you soon develop a method and (touch wood) i've not had any problems. I made my own "T"s out of balsa wood, skinned them in carbon then having checked their angle of incidence (God i'm starting to sound like Wouter) bonded them on with Epoxy and some carbon tape. The effect they have on the boat is astounding, the bow starts to go down, the rudders kick in and WHOOSH of you go faster than ever. They also contribute to a performance gain upwind as well. They act like a sort of "lateral damper" reducing the sort of "hobby horse" effect that you sometimes get on tidal estuaries. I dont use in light winds as i guess the drag outways any gain - i think (wheres my slide rule They are not covered by any patent and as far as i can acertain are legal for F16s - assuming they're not canted ....... no lets not go there ! Being painted white you can easily see if they have got any weed and its pretty simple to either reach down and clear it or remove the pin and lift them. I've maybe made it sound really simple but i was lucky in that i was able to check and measure Jon P's production items. If there's any other questions feel free to ask.

Hi Mike,
- Did you put glass the T-foil onto the existing rudder, or make a new rudder in Balsa, add the T-foil bit and then glass the whole thing ?
- Got any pics of the rudders, either finished or under construction ?
- Do the cassette type stocks ever get jammed, a big concern while surfing a 4ft wave towards the beach.....

Steve

I am looking at T foils for my next boat. No good in this situation as they do not kick up !

Mike added foils to an existing pair of blades. The Stealth originally used the same foils as rudders and daggerboards (I think they were actually 49er rudders) - then most owners got the bigger R dagger boards and so had a spare pair of rudders!

I've never had a problem with rudders sticking. As Simon says, they don't kick up. But the big advantage is that you can sailo with them well up without the steering becoming really heavy - because you still have the correct profile of blade in the water.

I'm still not entirely convinced by the T foils though - in light conditions I'm sure they must crate more drag.

What if you were able to change the angle of the horizontal blade slightly so that it holds the sterns down in heavy air and lifts them a little in light air? (Or be able to change the fore-and-aft angle of the whole rudder slightly to achieve those effects?)

I guess I am thinking of sort of how the fins/wings work on outboard motors to control trim of the boat.

Currently John (Mr Stealth) has a Set and leave set up with approx 2 degrees of drag (I think) on the Stealth range.

Hi all,

on Int.14' Skiffs Lindsay Irwin uses a twist grip type tiller extension to adjust the angle of the vanes on the bottom of the rudder blade. Angled down to lift bow pull transom down downwind, angled up to give lift to transom upwind. He swears by it and claims it is easy to operate once set up. But it must create more drag as it has more surface area than standard blade and when used to trim boat must create drag, I guess not as much as transom dragging or bow under water though.

Yet again played around with this sort of thing on sailboards years ago, but found for speed you couldn't beat a properly foiled straight fin with no extra bits on bottom. Of course sailboards weren't battling nosedive or transom drag though.

Maybe I will talk to Linsay some more? Definetly would be a weed catcher though a big problem on my home waters.

Regards Gary.

G'day All F16 Enthusiasts. This is my first post to cat sailor, so here goes....

My Name is Marcus Towell & live in South Australia.

I have been perusing some of the many posts within the F16 forum & have found the discussion interesting.

The Blade F18 was our project here in Aus & I am now looking to build two Blade F16 to replace my Marstrom Tornado.(If anybody is interested in any photo's of the blade just ask)The Blade F18 is going well & continues to improve when our development timetable allows.

I too am very keen to see some photo's of the T-foils as there some serious 14 ft skiffs at our club that use a similar system ( their trim foils are actually bigger than the steering foil !!)

Looking forward to reading future posts.

Marcus

The horizontal foils are bigger than the vertical rudders?! Bigger in what way -- in volume, in fore-and-aft dimension, in side-to-side dimension? (Sorry, but I don't know the correct terminology for describing these things in engineering terms.)

Marcus, Welcome! Look forward to hearing more from you in the future.



I'm interested. In fact I think I could speak for many here and say we're interested. Would appreciate it if you could post some picture here.

Thanks in advance.

Mark.

What a perfect time to use this image.

And here you have them :

Note the white foils are of 2002 the Black ones are newer and more faired.













And now for a work of art !

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I second Marks comments

Wouter

Wouter,
What are those pictures of? The Stealth?

Pictures are all of Stealth F16's; The white ones are off a UK based boats and the Black ones are off a US based Stealth F16 in California. Of Mark Talla. Eric Poulsen took them when he went up there for a sail in 2003 I believe.

There are quite a few T-foils in the F16 class at this moment. Currently all on Stealhs but a large portion of all of the Stealths produced have them. The other builders (except VWM) have looked at the setup and even had a test sail with them. I don't know wether they will go for the T-foils as well, maybe Marcus will. I personally still have to test sail these but that is planned for this spring at the Dutch Stealth Agent.

All very exiting.

Wouter

Welcome to the group Marcus,

It is a great honour to welcome you and your friends to the F16 class. To be honest; guys like you are very valuable especially at this time of growth. I'm thrilled with your decision to go with the F16's for your personal craft. And I'm quite sure the baby Blade (to the F18) will proof to be a little kitten with a big roar.

I've posted a few pictures of the T-foil rudder system in reply to your request. The foils on the stealth are much smaller than the I-14 because their function is a little different. The F16's are not as nervous as the 14's and more control can be left to the pilots. To foils on these cats only slow down the undesired movements to a level where the crews can adjust the trim in a comfortable way. That is all that is needed. Any excess funtionality will only lead to unnecessary drag and level-off the peak performance of the craft. Everything is a trade-off and one can loose as well by overdoing on a good thing. I really don't there is any benefit to large surfaces as the F16's are more controllable in basis and don't have to fear a wipe-out as much as the little skiffs.

And I second Marks comments that we all love to see pictures of boats in production/assembling.

Good luck,

Wouter

(co-founder & Chairman F16-class , 32, The Netherlands)