how to determine sail area

The rest of my FOOTBALL sketches

Here's the rest of my scaled sketches for my FOOTBALL design concept, in case Stoned or anyone else is interested. I will re post the 1st one as well, so all three will be together. I found them while going through my papers, looking for something else.

 

Thanks for posting that Sharpi.

Very cute little boat.

I like the idea of having the square bow, eases the curves and creates more space.

Also being chined, looks like an easy to build boat too. Could even stitch and glue it.

Lot of ideas there to work with.

Cheers

 

Thanks for the kind words.

It is designed to be extremely easy to build. There is no twist in any of the sheeting and there is no need for timber stringers either The shelves and the frames form a very strong 'egg crate' structure. The direction of the surface grains of the plywood will have to be watched. Especially if three ply exterior grade is being used. For the hull sheeting, they will have to run across the shelves and keelsons.

It will consume a surprising amount of plywood. I would not be surprised if the hull alone ended up weighing around 300 lbs. The keel, along with its steel reenforced concrete ballast slug would probably tip the scales at another 300 lbs.

You are right. The chines are to be stitched and glued and not have chine logs. There would be a sheer clamp, though, and it would be the hardest part to make, because it would have to bent in two planes at once.

If I had the money and a slip to keep it at, I'd build one for myself. I'm sure it would draw a crowd wherever it it was seen. And the boast that it could cross an ocean (though, if I owned, it probably never would) would add more to the spectacle.

Sooner or later, I would have to add credence to such a boast, so I would take it across one of the Great Lakes. And if that voyage went well, who knows?

I would never, never, take it on an off shore voyage until I had a good long time, maybe three seasons or more, to learn its ways in a wide variety of conditions.

I think that is how Donald Crowhurst got into trouble. He took a boat he had never before sailed, that was of a type he never before sailed (a trimaran), on an off shore voyage.

For some reason, the amas (floats) of both Crowhurst's and Tetley's trimarans leaked. Had they had their boats three seasons or more, the problem may well have shown up and been dealt with, before the start of the race. If that had happened, who knows? That may not have only changed the outcome of the '68 Golden Globe race (with RNJ coming in first, only to be upstaged by Tetley making the fastest passage) but the development of yachting as well (the reputation of multihulls getting a tremendous boost).

It is interesting to note that both Moitesier and RNJ had had their boats for a considerable amount of time before they entered the race and had extensive off shore experience with them.

Tetley had sailed his trimaran around England with a crew once, but not across an ocean. He had the trimaran five years before joining the race, but the amount of off shore experience with it is unclear. He and his wife lived aboard it.

As can be seen, all three of them would have finished the race, if Moitessier hadn't dropped out and Tetley's trimaran had not broken up. So I stand by my rule: Know your boat.