I have finally finished the Quill wingsail with camber control servo. Next I'll test it out before the lake gets to cold.

Hello Dan,

Very interesting reads on your wingsail projects. I didn't read every single posting on the other thread, so please forgive me if this has been discussed already.

You said in the previous thread that your wingsail catamarans are very skittish because you're running without ballast (as a cat shold be sailed). This of course is just as one would expect; at model scales things move too quickly for the pilot to react.

Have you considered installing a helicopter-type heading hold gyro on the servo that controls angle of attack of the wingsail? With a heading hold gyro the boat could make instantaneous adjustments in wing pitch, thereby largely (if not entirely) eliminating capsizing.

Jim

Jim, That sounds very interesting. Question, Does using a "heading hold gyro" with a servo do away with the need for a channel on your radio contoller? One of the problems I have is most "Surface" controllers for boats only have 2 channels. I've resorted to using two radio control units for the catamaran, one for rudders and winch, and the other for the camber servo.

A heading hold gyro would plug in line between the receiver and the servo that controls angle of attack on the wingsail, so in that sense it doesn't require any extra channels. However, that said, it's best to set up the gyro with separate gain control so that you can dial down the gain (to keep the gyro from being too hyperactive). That requires a second channel.

Because so many guys in the heli world are converting to flybarless control systems, you can find heading hold gyros at very reasonable prices on the Heli FS/W forum. You can expect to pay around $60 shipped.

Examples of reputable gyros that you can find in this price range would include Futaba GY401 and Align GP750. I have lots of experience with both these. I personally don't bother with the really cheap gyros, although some swear by them. Note that some gyros (like the GP750) REQUIRE a digital servo; these will burn up a regular analog servo. The GY401 on the other hand can work with either digital or analog servos.

As for channel availability, back in my RC sailing days I used an aircraft-style transmitter. The stick for rudder control worked fine because it was like a tiller. Naturally if you're on FM, you'd want to get a module-style Tx and swap the 72 MHz Rf module for a surface unit.

I'll be glad to discuss this in more detail if you're interested.

Jim

Yes, I would be very interested. I wonder if you could suggest a transmitter that could be adapted to control tandem rudder servos, mainsail & jib winch, wing camber servo, and gennicker winch? I'm trying to incorporate all the sailing functions of the AC45's into my model. I've even considered making it a two man job, one controlling the mainsail winch and steering, while the other controls wing camber and deployment of the gennicker. It may be a bit ambitious but I'd like to do it all from on transmitter.

Dan, I can quickly get out of my depth here since I don't do model yachting, but it sounds as though you'd need 6 channels, but I'd aim for an 8 or 9 channel radio so that you have have the TYPE of control you want.

For instance, tiller could be on the left stick (Mode 2), but winches you might want to control with a three position toggle switch - center off, down reeling in and up playing out on the sheets. Gyro gain takes a two-position toggle switch - up for heading hold and down for rate.

Here's another approach: You could have wingsail control on the right stick. Up and down could control camber, and left and right could control angle of attack.

I'm sort of thinking out loud here, but these are some of the options.

Are you running 75 MHz or 2.4 GHz? The latter would allow you to use an airplane radio with no mods.

Jim

I am currently using a Spektrum DX 2.0, 2-Channel 2.4GHz DSM Radio System. I really like your idea of using the Right stick flight controls to control the Wing's reach and camber. Using a three position toggle switch to deploy the ginnicker could also work. And, Left stick could control the rudders. All great ideas Jim. I'm starting to see how one might use a airplane radio to control the Cat just like a plane. I've already created plans/templates for a new longer set of hulls, and a slightly shorter Wing in anticipation of a need for more room for extra winch and servo (more wieght) but first I'll use the set I have to test theory.

Dan

I have been searching the internet for a way to build a RC AC 45. I would like to ask you about your hulls. please email me at patrick@compositeyacht.biz

Patrick Edwards

Dear Elliot,
I am an engineering student from Barcelona. I am doing a project about building a sail boat with a rigid wing sail, and I will be thankful if you could help me answering the following questions.
- Which materials have you used to build the strucure of he wing sail?
- Which wing sail perfil have you used?
-How have you build the structure?
-Could you explain us the mecanism to move the wing sail?
Thank you for your time and I am looking forward to hearing from you,
Dr SAILS

Check out my thread on this website. Boats; Sailboats; Wingsail Catamaran. In this thread I have plans and photos of the Wingsail construction. If you e-mail me at; delliott@1220.com I can send you a AutoCad model. Happy to help. Hope to hear from you soon.