Naked Canting Keel

From the world of big boats comes another canting keel-but this one is different: it has no daggeboard ,forward rudder or wings to make up for the loss of lateral resistance due to the canting of the keel fin.
Grant Wharrington’s new Wild Thing is designed and set up with a canting keel that has limits on it that can prevent the boat from heeling more than 10 degrees with the keel canted to its maximum. This limit is specifically to allow the boat to compete in the Sydney -Hobart race.
The designers say that the boat has no additional lateral resistance because they expect to derive all they need from the keel fin since the keel doesn’t cant much. My guess: they were referring to just the configuration they need for Sydney -Hobart because why have a canting keel at all if it is not going to cant at least 40 degrees? Schock 40 and I think Wild Oats= 55 degrees to each side. And the new 116’ Maiden Hong Kong with her
canting keel max over causes THE BOAT to heel 37 degrees(not the 10 of Wild Thing).
The model I am building with a canting keel will heel close to 50-60 degrees- just guessing- with the keel max over!
And I’d be willing to bet that when Wild Thing is not in her Sydney-Hobart configuration she’ll sprout some form of extra lateral resistance–upwind at least and that the keel will move much further.

Doug Lord
microsail.com
monofoiler.com
High Technology Sailing/Racing

Doug,

You have to remember that full size maxi boats are all rated under a hadicapping rule of one form or another to correct their speed differences. The 10 degrees of static heel is compliant with one such rule - the IRC rule (one of the biggest offshore racing rating rules). So this boat will more than likely sail all the major offshore races with the 10 degree static heel limitation in effect.

They may have some other configurations for some specialized races (where they sail under the PHRF rule or some other rule for example). But remember, when they add more speed to their boat, their rating will change as well. So if they add 20 seconds per mile of speed potential, the will also take a rating hit of 20 seconds per mile. So there is, in theory, no advantage of adding more speed to your boat. The handicapping rules even it back out again. Of course no handicapping rule is perfect, and everyone tries to build rule beaters. But the bottom line is that racing is not necessarily about having the fastest boat, but having a boat that can sail up to her potential.

For example, I have seen well sailed 1970s vintage IOR boats that are well sailed beat the best turbosleds on corrected time. The Transpac this year was almost won by a Cal 40 (not even the fastest high tech boat you could buy when it was new in 1964!).

The IRC rule is set up as a balance between outright speed and safety. The boat must be able to recover from a broach or a full capsize. As such, it must maintain certain stability limits. The IRC rating comittee has been concerned about safety since the beginning - even before the tragic Sydney Hobart Race a few years back where a number of sailors lost their lives. All offshore rating rules take safety into account. The Volvo 70 rule places strict limits on the inverted stability of the boat.

With this in mind, limiting the cant of the keel allowed the designers of Wild Thing to go with a narrower beam and still meet the safety and stability limits. Alternatively, they could have gone with a wider boat and increased the cant, but they saw that as a slower option for the races they want to compete in.

So if these guys do change their boat around to add some more foils and increase the cant of their keel, they will do it because there is an rating advantage, not because they want another half a knot of speed downwind. And the way the rating rules are currently written, there are not many races where Wild Thing will be able to beat the rules with such a configuration. One exception would be if they wanted to take line honors in some downwind race (like the TransPac) at the expense of the overall win. Then they might lighten their load a bit and go with more cant. Of course with such a downwind dominated race, they probably would not need extra lateral resistance…

  • Will

Will Gorgen

Will, I’m not sure what the 1.61 limit is and am not really interested since many people are upset that such a limit has been imposed on the Sydney-Hobart including Nevile Crighten(sp?).
I think any rating rule that leads to low performance boats -or boats that are a lot slower than they could be is past its time.
Maybe the maxZ86 class will take off and true “max speed” yachts will race
all over. Or maybe the rating rules will be improved to allow max speed boats to race. There are more and more boats all the time designed simply to go fast and the rating rule(s) be damned. “maxi” should mean maximum speed in my humble opinion.

Doug Lord
microsail.com
monofoiler.com
High Technology Sailing/Racing

The idea of any rating rule is to create an even playing field for folks to compete. The rules are setup so that a boat can hopefully remain competitive for many years. Some rules, like PHRF are designed to allow your average sailor with a 30 to 40 foot racer/cruiser to compete. Other rules like IMS and IRC are designed for the Grand Prix multi-million dollar campaigns. But even the guys who are spending those millions of dollars on their new boat would like to keep it for at least a few years.

Lets suppose that there was no rating rules at all. What would the fastest boat in the world look like. Mari Cha is a pretty good prototype. As is Playstation. So if you could not build a boat faster than Mari Cha or Playstation, then why bother. My guess is that the only thing that would limit the speed of a boat would be the pocketbook of the owner. you would end up with 3 or maybe 4 boats bothering to show up for any of the major races. Even local racing would be dominated by the local “rich guy” who could build the biggest boat that would fit on the local lake. No one else would stand any chance of winning and many, I suspect, would never even show up. They would go participate in some other sport that they could afford. Or if they loved sailing, they would simply cruise.

People are always going to complain about the rules. IMS has its critics - folks who complain that the rule encourages very unsafe boat designs. PHRF has its critics as well - people who feel that their rating is somehow overly harsh. Heck, even one design rules are constantly under critique (look at the Farr 40 rules and the dispute over the owner/driver provision). As you note IRC also has its critics. This is a normal (and healthy) part of the rating process. Rules come and go. The Americap rating system in the US is trying to pick up (with limited success) where IMS left off when it died over here. when Americap was being concieved, the criticisms of the IMS system where taken into account in an attempt to make a better rule.

The latest rage seems to be Box rules (length, beam, draft, displacement, Sail Area) such as the TP52 class. I think the MaxZ86 rule is also a box rule? The MaxZ86 will produce some very fast boats. But will they be as fast as the 140’ Mari Cha? Probably not. Will they be as fast as the 120’ Playstation? Definitely not. So are they really Max Speed?

If you read the rules breif for the MaxZ86 class: http://www.maxz86.com/rulepromo.php you will see that the intent of the rule is to create boats that are evenly matched - not as fast as humanly possible. There is an emphasis on safety and longevity of the class in addition to speed. They rule out specific things that could have produced faster boats like hydrofoils or multihull platforms. They place limits on the major speed producing factors like length, sail area and stability. Sure, they are going to be faster than the SC70 turbosleds that came before them. But the goal is not maximum speed, but even speed.

  • Will

Will Gorgen

I like box rules for models or full size-as long as they don’t have too many absurd restrictions.It’s great that there are boats like Mari Cha ,Maiden Hong Kong and Genuine Risk pushing the limits of monohull technology as well as the big multihulls built for pure speed.

Doug Lord
microsail.com
monofoiler.com
High Technology Sailing/Racing

What happened to the Little America’s Cup. No one challenged for 7 years, so they had a one design race. If you don’t have the money to build a faster boat why try.