Swath and hydrofoil as a hull for Kiteboat

[Hacklebellyfin]

What are the pros and cons using swath and hydrofoil hulls designs for Kiteboat ?

Thank you

[Guest625101138]

The cons are slow and unstable. Cannot think of pros.

Rick W

[eponodyne]

Swath hulls probably wouldn't work as there are too many variables to allow them to run at their intended draft. Hydrofoil hull design *might* work, but probably not on all points of sail.

If you could get the SWATH hull big enough, probably 40 foot and up, that might be a good place to start. The hydrofoil idea is appealing in the extreme but honestly, why not just go with a planing hull? In my latest mental iteration of a kiteboat (still in the cocktail-napkin stage), I'm thinking of twin Slicer-style hulls of about 26'x3'6" each, with a small center "pod" housing the crew and kite controls.

Probably ought to talk to Kengrome about that, I ort ta!

[blackdaisies]

You might make a pontoon boat with rocker and have a daggerboard on it, a centerboard or a drop keel type manually operated for stability. The pontoon is not very good on ocean water, but they are white water rafting on blow up ones with rocker. The pontoons look like upturned bananas with a chair in between. If you don't have some rocker in the pontoons, you will just run into every rock or wave under water and sink your boat.

[masalai]

No.... :d:d:d

[blackdaisies]

There re ways to make a pontoon boat more sea worthy, but not worthy enough for the ocean. They say to add a 3rd pontoon in the middle, plus add a metal top to the bottom between your pontoons. It will make it stronger and make sure you a have pontoons that are not just a hollow tube, you need with braces every so many inches. Pontoon boats are not for oceans, but if they can white water raft in them, they can build a small sailing craft out of them. It would be experimental, but it would work. I wouldn't go voyaging in them, but you might get a better pontoon boat and add rocker to the ends so it will ride above the waves instead of straight through them, it would at least work better.

[Hacklebellyfin]

I thought about the raft or pontoon.

Some fishermen in Myanmar are fishing about 100 miles offshore for months on bamboo raft anchored.

They were doing it in any weather till the last typhoon this year. (no news about them)


About foils and Kite:

[Hacklebellyfin]

Epo,
what do you mean by twin Slicer-style hulls , this tread is the sole reference in entire google with this concept name.

keep posting you are interesting to me!

[eponodyne]

In his book Boats with an Open Mind, Phil Bolger designed a boat he called Slicer. It's a panga, really, with a monohedron bottom designed to make good use of plywood. My thoughts for a kiteboat catamaran put the rough dimensions of each hull at 26x3.5. that's like a 7.5:1 length-to-beam ratio and I don't know how well it will plane, though. Kengrome is the fella on here doing all the cool design work in this area. Look through his galleries, and expect him to win Professional Boatbuilding Magazine's "fun and fuel efficient boat' contest in April of next year!

[Alan_VA]

Short answer follows: The SWATH hullform has a large surface area for a given displacement and a correspondingly large friction resistance. They are, however, very non-responsive to wave action. These two attributes combine to make them a nice, stable platform suitable for straight lines at constant speed. Kites, on the other hand, need to be able to respond quickly to changes in wind direction and speed in order to stay in the air. Putting the two together seems like trying to use a gazelle to pull a plow.

Alan

[eponodyne]

Kites, on the other hand, need to be able to respond quickly to changes in wind direction and speed in order to stay in the air.

Not at all. I would like to formally request that if you (General "you," not intended specifically for anyone) haven't spent at least a few hours flying 2- and 4-line kites in several sizes, that you refrain from posting conjecture about what kites can and can't do. The idea here is to add to the knowledge base, not simply parrot things that are demonstrably untrue or to pooh-pooh poorly understood concepts.

...like trying to use a gazelle to pull a plow

Great analogy. I am totally going to rip that off!