Canting Keel Mechanisms

when you can get the bulb near the surface, than more heeling would get the bulb ( weight ) out of the water, giving another stabilty curve but also drag pic,
lets keep thinking ;-)

 

Move...something....

Well, the next area is going to be combinations of fixed or canting keel and on-deck ballast supplemented by buoyancy pods. Two big "Maxi Skiffs" are (apparently) being built using examples of this technology by Sean Langman and Bethwaite/Bulloch...

 

Per The Yachts & Yachting diagram:

I'm thinking quadrant gear with a worm somewhere near the cabin top.

Don't use the "it takes too much room" argument with me. I'm a trailer-sailor: 4 crew on an 18' boat for the weekend. 10 guys on a 70 footer sounds luxurious. Besides, according to Campbell Field, the navigator is not even allowed to walk on the leeward side (where a quadrant would be - opposite to the keel cant) to get a drink of warm water.

If you love hydraulics, then drive the worm hydraulically. But lose pressure, the worm is not likely to free-wheel. A bobby-pin could lock the keel in place.

 

Worm Gear

I found this on the Volvo Ocean Race sight:

Following the 2005-6 Volvo Ocean Race, the VO70 rule will be developed further to apply the lessons learned on the last event and ensure the continuing evolution of this outstanding class.

The basic design parameters will remain the same, but as a result of meetings with the teams and interested parties in Melbourne and Portsmouth during the stopovers, changes being considered include different engines and generators to produce more horsepower, as the teams on the last race found they were not always able to cant the keels as fast as they would like.

Another area of possible change is the canting keel actuation system itself: will the boats have hydraulic rams or will they use, for example, the new SKF/Semcon ultra-low friction worm drive system?

The VO70 Rule Version 2 will be released in September 2006.

 

Priorities

Not sure here if the priorities are beeing put in the right order. Missing something about reliability.

 

In my opinion The Volvo boats, shouldn’t even be allowed to be called sail boats.

 

well the "more horsepower comment", was in relation to the engines that cant the keel, not the SA/D ratio. Cayard had issues gybing the Black Pearl in heavy winds because his keel moved slowly.

 

Here we go again...

Quite an absurd comment, in my opinion.....

 

In my opinion the canters should be human powered. I can just picture the Volvo's 10 years from now; 400 HP disels pumping out black smoke.

 

It's amazing how fast you can get a boat to go if you have enough horsepower.

Just think with enough horsepower you can reduce the number of crew to 3-4 and not have to worry about pesky running rigging, fragile sails, and expensive CF masts ...

 

Sail boats should be 100% powered by sail. Using engines to produce power to move 'bits of boat' is just wrong. It should be man and material vs sea.

Else they should do away with the rags and sticks, and place bigger engines and propellors. Hey = power boat racing!

 

verytricky - why not do away with winches, etc. as well? They are mechanical devices as much as motors......
Sadly, the Volvo boats are dependent on a design criterion that demands they be good round-the-buoys as well as offshore. If you make the keels cantable solely through man-power (hydraulic pumps, grinder/generator electric motors?) then your objection to stored anergy is removed. Many of the early canting single-handed boats were man-powered, dsince there was little hurry to tack. THose boats are, however, appallingly painful to sail in a harbour if you cant the keel.

Steve

 

"Normal" sailing winches may be mechanical, but they require manual input. That's surely different from a powered keel.

I've been trying to think of an analogy to powered canters in anothr sport. I can't. That surely is significant - it seems that no other sport (apart from designated "motor sports") uses motor power. Either you use a motor (in which case you're a motor sport) or you don't. The fact that there is this differentiation seems to me to be enormously significant.

Using power for information is normally excepted. You can use batteries to power your radio for an Everest expedition, batteries to power your bike computer on a pushbike, or an auxiliary to run your instruments on a yacht.

However, if you get stinkin' great batteries and connect them to a device that drags your gear up Everest while you walk along behind; if you get a bunch of batteries and connect them to an electric motor that drives part of your bike rather than just providing information; or use the donk to move ballast, then arguably it's not in the same category.

 

How is having an electric cart dragging your supplies up Everest different from having a Sherpa? Either you carry your own stuff up or you don't.
If you winched yourself up Everest, would that still count? Even on skis?
Obviously, there is no cut and dried answer, but I totally agree that having larger and larger engines to cant the keel is contrary to the spirit of the sport.
Steve

 

canting

" ....larger and larger engines to cant the keel is contrary to the spirit of the sport". I'd bet that any designer of any canting keel raceboat will opt for the smallest possible engine or engine/battery combo to get the job done properly. But the problem is that so many seem to think that doing the job(moving ballast) in the first place is against the spirit of the sport.
I don't; I think it is in the finest traditions
of sailboat design and produces magnificent sailboats that have brought monohull speeds much closer to multihull speeds than ever before.
Everybody(well, almost everybody) agrees that dinghies and sport boats that rely on movable ballast hanging out on trapezes produce some spctacularly beautifull sailboats and "sailing moments". So if technology can (finally) allow movable ballast to be used on much larger boats , why not? Why not appreciate them for what they are: spectacular, high performance sailboats!