CBTF(Canting Ballast Twin Foil)

[gggGuest]

Originally Posted by Lorsail

gGuest, my only point was to rebut the ridiculous assertion by CT249 in post 150 that CBTF boats violated the normal rules.

But Doug that's not a ridiculous assertion. According to most dictionary definitions of normal its quite correct. Motor driven canting keels wouldn't be legal in any race I'm likely to start this year for instance, and for that matter there are features of the various boats I sail that wouldn't be legal in any race a MDCBTF boat is likely to start this year either.

However exceptions to those normal/default rules are very common, so its OTT to make a very big deal out of it. But because these are legitimate exceptions made by class or event organisers to say it is legal under the racing rules is arguably misleading. It would be better to say that there are circumstances where it can be legal.

Chris you're pushing too hard again with your "no races for trap against non-trap" boats. There are not to my knowledge any Interntional events for unballasted boats where the racing is not within a single class rule so that's hardly suprising. In the UK at least there are numerous major open handicap events where dinghies with all sorts of different exceptions to those parts of the racing rules race against each other, so again its no especial big deal. In fact the only reasonably international multi class event for unballasted boats I can think of is the round Texel Cat race, and that does mix trapeze and non trapeze boats.

Now will you boys settle down and put down those bottles? This place is worse than SA for dogmatic opinions pushed to the limit with dubious real validity!

One LAST time:
ggguest, 249's suggestion was that CBTF boats were violating the normal rules which I still stay is a ridiculous assertion!
Of course that depends on where the section on "normal" rules ends.
It is my contention that because 86.1 SUPERSEDES almost all other rules that it is in the "normal" section of the rulebook. But as I said before I still have my 2004 rulebook and the normal vs abnormal rules are not clearly deliniated.
Again, the fact remains that when CBTF or canting keel boats race they do so legally under the Racing Rules of Sailing.
And ,generally speaking,40' and up, they'll beat the hell out of any "normal" boat!

[CT 249]

Originally Posted by gggGuest

Now will you boys settle down and put down those bottles? This place is worse than SA for dogmatic opinions pushed to the limit with dubious real validity!

Ya, I agree with that....just make one little tongue-in-cheek comment and suddenly you're the anti-Christ.

In "real life" I rarely stir people up in such a way, but it's hard to avoid it here sometimes. The net is a place that brings out many of our character flaws, isn't it?

[Andy P]

And we must thank CT for bringing rule 52 to our attention regarding foilers in the int moth class!
No action yet on a rule change , so still technicaly illegal.

[usa2]

isnt the moth a "developement class" which means your are allowed to experiment with foils and etc.? Its like saying Australia 2's keel was illegal in the 12 metre class. 12 metres are technically also a developement class, so therefore it fit into the measurements and wasnt illegal

[Andy P]

int moths are a development class- ie you can do anything if it's not banned ( eg sailboard or multihull config are about the only things not allowed)
Foilers are allowed ( cos they are not banned )

but the control system --- rule 52 says appendages can only be adjusted by manual power - using wands or similar for adjustment is not using manual power!

Rule 52 can be opted out of ( as mentioned above ) , but requires a vote / rule change in the class.


is the manual power in rule 52 the reason why winches are not pedal driven?

[usa2]

the manual power in rule 52 would mean that electric/hydraulic winches are illegal if it was. not sure what different events allow/disallow them. I know the Sydney to Hobart allows electric winche, as Skandia Wild Thing had them. The Transat organizers used to say that the record wouldnt be official if you broke it using powered winches. I think that may be why Mari-Cha IV has pedastals rather than powered winches, as she was after the transat record.

Andy, it seems to me that if the Moth Class rules specifically say words to the effect that you can do anything if it is not banned that that effectively trumps Rule 52 under the authority of Rule 86.1 (c)("Class rules may change only racing rules 42,49,50,51,52,53 and 54." Is that not true?
How were the recent worlds and Aussie Nationals run with the rule 52 thing hanging-what prevented protests?
As to CT , he was one of the leading supporters of foils in the Moth Class(NOT!)
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I couldn't download the current Moth rules but I found this dated Oct. 1999 . If this preamble is still there I can't see how any protest under Rule 52 could be valid:
"The International Moth is a singlehanded development class boat.
The intention of these class rules is to give the designer and builder fullest liberty in design and construction,within these rules, to develop and produce faster boats."
Since there is nothing in the rules that prohibits a wand under this preamble I sure would think it would have to be considered legal. But apparently there was a protest using Rule 52 at some recent regatta that was upheld-can you elaborate, Andy?
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Mandatory CBTF content:
USA2: wasn't Magnitude 80 a"TMF(BTP-beat the patent) boat? And wasn't it just beaten boat for boat by Pyewackett(CBTF)? Must have been because Pye was bigger,huh?

[usa2]

Yes, they finished about a mile ahead in light airs. While Pyewacket(CBTF) did well, 90' CBTF Genuine Risk was beaten by Mag 80 and a 70 footer with a cruising interior. Your using the term "beat the patent" is sort of a childish use of words, as many of the boats not using CBTF are doing so out of practicality, rather than trying to get around the patent. Of course, CBTFco is an American company, and here in america people will do anything to be able to make money off anything, so therefore it is understandable that someone had to patent it. Alex Simonis, designer of Nicorette 2005, said so himself that CBTF is not suitable for boats in the Syndey to Hobart race, or in most ocean racing in general, because the forward foil is not neccasary all the time, and is vulnerable up forward. Also, control is a problem when boats fly out of the water. Its a safe assumption that AAPT would have won the last Sydney Hobart if Nicorette had been CBTF

Well, lets see how the transpac goes.
By the way,I think the old Wild Oats was entered in the Sydney -Hobart and retired due to an electrical problem not related to CBTF or her canting keel-seems the owner thought that CBTF was suitable.And then, of course ,there was the Bermuda race where the two CBTF boats beat a third maxZ86 that had water ballast.
CBTF is the only lateral resistance solution for canting keel boats that is patented(except for the kFOIL) and there are boats racing today
that have used other systems because of the perceived high cost of a license. If you want the best it costs money....

[usa2]

maybe next year Genuine Risk will go up against Nicorette. That would be the most fair test, as both are 90 feet on deck with a bowsprit. I question your claim that its the best. It certainly is better on some points of sail in some conditions, but the TMF systems is the only one that reduces the wetted surface, which makes it much better off the wind. The CBTF system only has its true benefits hard on the wind. Do you know whether there are maxis being built/planned with CBTF? All the new ones seem to be going with the TMF-type system. Also, "CBTF is the only lateral resistance solution for canting keel boats that is patented(except for kFoil) and there are boats racing today that have used other systems because of the percieved high cost of a licence.." First of all, didnt Andy Dovell patent his wings? Secondly, they are only patented because some people figure they can get rich off it. Imagine if someone made a company called RudderCo and everyboat that has a rudder has to pay them a fee. That would be rather stupid.
Wild Oats dropped out because of flooding that damaged the electronics, which in turn impaired her ability to cant her keel. Its probably a good thing she didnt go to sea.
I honestly do think that the CBTF MaxZ86's will win line honors for the transpac, barring any bad weather that damages them. They are the biggest boats allowed into the race,so their competition will be eachother and some smaller boats.

Sorry, I forgot about them-I know he was going to patent them but I'm not sure he did.
According to the CBTF guys the nature of the twin foil system improves handling off the wind (tracking)as well as increases speed because of their location relative to the bow and stern wave.Further, no other canting keel solution can manouver as quickly or turn as tightly as a CBTF boat.The twin foils allow the balance of the boat to be more precisely controlled than on any other type of canting keel boat by varying ,independently, the angle of incidence of each foil over a wide range.No other lateral resistance solution offers the windward ability of CBTF for sure. No other lateral resistance solution offers the controlled ability to move directly 90 degrees to their course to weather for short periods in tactical situations. Wild Oats(#1) famously used this facility in front of a large number of spectators or press, if I remember correctly, in the Hamilton Island race in 2003 where she beat ,boat for boat, boats 20' longer than she is.
I think it is the best racing system for canting keels period. Only time(and maybe a little research) will tell for sure...

[usa2]

CBTF is obviously the best system for going upwind. But once you come off the wind retracting that forward foil on a TMF type boat gives it a big advantage if the boats are the same size. There isnt any need for that forward foil off the wind. A retractable CBTF system would make a lot of sense. Do you know if they have looked at that?

Listen, the position of the forward foil increases speed relative to other canting keel boats that don't use this system. You should try to realize that they (and others) have tested this pretty thoroughly and that it is a fact not speculation; an illustration concerning this is on their website under "Tech". It reduces wavemakng drag....
No way would they get rid of that foil: it is too important for the reason stated above both upwind and downwind as well as improving the boats tracking off the wind in a seaway as compared to other canting systems and fixed keel boats.
Now, in extreme light air when wavemaking is not an issue you could have a point...

[usa2]

but if others have tested it pretty thoroughly, why have they not used the system. I understand that some boats maybe have done away with it because they didnt want to pay the fee because it is patented. Skandia and Nicorette both tested CBTF configurations-Skandia i think did want to avoid the designers fee, and at first that boat didnt have any sort of forward foil. Nicorette, on the other hand, wasnt built on budget, so the designer looked at several different configurations and decided after tank testing that CBTF would hinder the boats performance off the wind. I actually know that this stuff isnt speculation, as I was involved in planning a "Spirit of Tradition" yacht that may have used CBTF or TMF. The project was cut after the guy building the boat decided he wanted a less complicated boat. We would have used a retractable forward rudder for the forward canard, as we found that CBTF under most conditions is far superior on the wind than TMF. Off the wind, we found that the boat made less waves and was a bit slower. We than took the forward foil off and found that speed improved. The client liked the CBTF upwind but wanted the boat to perform well all around so we figured why not retract the forward canard.
And two rudders are generally better than one, but with one set so far forrward it is capable of causing problems.