Wow love the ideas that come forward here I have seen this type of rig on a water
yacht If I am not mistaken I think its called a Luna rig
I will be interested to see the comments as to its suitability for landyachts as to
centre of effort, resistance, etc etc by people on this forum who know these things
Cheers Hiko

I think it would be interesting to try, if only as a learning exercise. The "old rules" of coinciding centre of effort, centre of lateral resistance and centre of gravity would be difficult to achieve, but perhaps a new take on this may succeed?
Forestay strength, I see no reason why this would have any higher loading than any other soft sail, and perhaps less as there is no leach to control, although a bit of roach may help the twist! I used (as per the rules of the British Association) a 5mm forestay for a Class 3 as in my avatar. 7.35sq m and around the 70mph recorded.

LOVE IT, LOVE IT, LOVE IT, LOVE IT,
Have a read of this en.wikipedia.org/wiki/Mast_aft_rig
with landyachts the biggest restriction on speed is aerodynamic drag, the mast system you have might cause lots of aero drag, but that can be reduced with some trickery

Gidday Blew, I also like it, a lot...do you have any measurements available?

Have to be a "Classic Class" Woodn-it-b-better [great name]

Yerh, also wearing me sox, no wonder i cant find them !!

How about this taking the design just a little further... "A" frame mast, the mast/s could be made as an aerofoil shape reducing drag and increasing the sail area as wing sails are very efficent.

How about removing sail leave aerofoil masts as wings keep forestay and go with that

Hey guys,
Love the ideas of the airfiols as a mast and as the stand alone power. Kind of defeats the simplicity angle but it is definitely interesting. As for dimensions the wheelbase is about 6' to 6 1/2' width and about 8' fore to aft. It would still be a mini of sorts. The mast being 15'- 16' long. It could be airfoi shaped fairly easily to help with the drag issue. The sail would end up in the 45-50 sq. ft. range. The size is mostly derived from where I have to sail it, which is small school parking lots. In those lots we cannot achieve full speed anyway. It is fun and makes for some close racing. It is kind of like playing chicken. You go as fast as you can for as ong as you can and hope you can make the turn with out crashing. If you look at my photos you will see one pic where I didn't make a turn I my buddies yacht and ended in a snow pile at about 25 M.P.H.. Thanks for the input I will stay in touch wth my development.

kiwi307 said...

Personally the question is; WHY NOT?
If it were not for experimentation your current yacht would not look like it does at all!

Haha, I agree - "If its not broken - break it". I love this new design!!

And its great to see you'll have oldMXer there to compare any improvments against.

Lighter still to use only a forestay and support the mast like any torque tube yacht, or get a bit trickier still and use a luff spar on the leading edge, could be a baby wing shape then!

I think the one weekend and and a dozen beers just sold me on going foward with the experiment. Thanks for the encouragement.

I'll raise that......a rum or two!!! [}:)][}:)]

Yes luff is the leading edge of the sail, so a "luff spar" is like a baby mast hanging on the front, normally very aerofoiled and free to rotate in line with the sail. Probably such an old idea that even landyacht won't have seen them!
Featured very strongly in a lot of the aerodynamics "bibles" as a good idea.
I think in this case it could link with the mast and provide some extra support, as otherwise all the mast has to cope with is a compression load.

Yes Paul but of course a luff spar was never used on a sail hanging from the BACK of a mast. They were on jibs and mast aft rigs only!

We will see if it is a good surprise or not. Planning on building the frame this weekend. One thing on my mind is whether or not the sail should have battens or not. Also am conserned if I will have a problem with mast bend under load.

I am searching for a used storm jib to use if possible if not I will make something. I have found a couple very close to my needs. That was the reason for my batton question because they do not have battons. I could always sew in some batton pockets though. I am also considering a laminated arched rear axle. I think that properly placed spreaders will help to keep mast straight if it is an issue. Should have chassis built this weekend. I will send pics.