Save-A-Boat - The Forum for Plastic Classic Rebuilds!

Check out this Cal 36 on ebay, it appears to have two rudders....very odd.
Jimmy Small
http://cgi.ebay.com/ebaymotors/1968-Cal ... dZViewItem

The one on the trailing edge of the keel is probably a trim tab, like the 12 meters used for years. I guess the theory is that by adjusting the trailing edge of the keel with that movable appendage, lift can be increased for higher pointing ability. Or something like that. These things never became commonly used. Is if because they only really work in specific designs or situations, or because of the additional complexity, I wonder.



Imagine sailing with these two tillers in your cockpit, though. That must be a bit awkward. Good for starting conversations with strangers, though.

I can imagine those tillers in a rolling anchorage with a running tide breaking the legs of yur guests as yur havin a bit of a nosh. not to mention a lovely way to really foul the mainsheet.

r

It's a learn-to-sail vessel. The student takes the helm of the keel-mounted rudder, but the instructor controls the spade in case the student tacks the boat across the path of an oil tanker.
Brilliant!

(oooooo! Mr. Cotter! I have another answer!)

Self-propulsion. Simultaneously scull the two tillers out of phase.

Anyone remember that pedal-powered Hobie kayak thing with the swishing underwater blades?

I had a dock-neighbor once who planned to mount swim-fin-like appendages to the after end of his hull (one on each side). The plan was that as the boat pitched in an ocean swell, they would propel the boat like fins on a swimmer do. I'm not sure if he ever implemented the plan (I bet I could find out though).

The designer couldn't decide between a full keel/keel mounted rudder and a fin keel/spade rudder, so he did both.

Rachel wrote:I had a dock-neighbor once who planned to mount swim-fin-like appendages to the after end of his hull (one on each side).

Did he by chance look like this?

That is possibly the best post I have ever seen.

George

...and you just know that it requried ZERO search-time because those pics are in Tim's screensaver rotation.

or is that a secret project Tim is working on?

Believe it or not my Dad designed the first trim tab- that's on the rudder for Sparkman & Stevens on Intrepid. It was controlled w/ a small wheel inside the larger wheel. The idea was to gain lift to windward by creating I guess a foil on the trailing edge of the keel- The wheel allowed you to change it port or starboard as you tacked. I also think it could be locked in with the main rudder to give you more rudder power. My older brother still has the working model of the whole gizmo Dad made to show Olin & Rod Stevens (sp?).

He also came up w/ the coffee grinders hanging under the deck rather than topside to get weight & windage below decks. I remember sitting in a chair in our cellar pumping handles with my arms and then feet so he could determine the best way to grind. Bottom line was hands were much faster but not as strong. That was fixed by shifting gears- which he changed from the old style of buttons you hit w/ a fist to a foot pedal that allowed continuous grindng. I don't think he was too popular w/ the grinders who spent the race below decks rather than up in the breeze!

There is no question about it, what you see is actually a FLAP. As the keel approaches stall speed the FLAP is lowered enableing the craft to land and take off with more lift at slower air speeds. Every pilot knows THAT! Heck, I know that and I'm not even a pilot!

Feetup, "Pilot to co-pilot..."