14 years old boy designing yachts

[kuba_sail]

Dear Designers!
I' d like to know an opinion of You, proffesional naval architects of my design, that I've added to Delftship.net site. It's called Casiopea. I'd like also to introduce myself, because I'm a new user, and It's my first post on Boatdesign.net
My name is Jakub Batog, I come from Poland and I'm 14 years old, as I mentioned in the title of my post. I'm building model yachts, that I've designed before. I love sailing apart from designing yachts (as soon only for visual effects in computer, but maybe some day, my designs will be sailing? Who knows? )

[Trevlyns]

First of all, a very warm welcome to you Jakub! We’re looking forward to great things from you in the future!
I searched Delftship.net but could not find anything called Casiopea. Maybe you could go to the link, copy the address and post it for us. I’d love to have a look!
All the best

[Quietboats]

You might try cliking this: http://delftship.net/downloads/showd...?DetailsID=243

Jakub, congratulations on your design and welcome to the forum! With the big masthead crane needed for the roach on your main why not consider a square topped main? I noticed the wings on the bottom of the fin keel. Can you describe your thoughts on why you included them?
Keep up the innovative thinking and learn all you can-good luck!

[kuba_sail]

Dear sir!
1) I've attached the "wings"(winglets) to keel for the same reason as the designers of ACC class (for example Alinghi Team, BMW Oracle etc.) attached them to their boats keels. The method of their working is something like that: They are using the losses of energy, caused by tip keel vortex, and changing them into energy that helps yacht to reach higher speeds. I've used the best (even better than eliptical!)- "fish-tail-shaped" wings to reachieve most of the loosed energy from tip vortex.
2) Why main is rounded instead of rectengular shape at the top? It looks better=)

Looks better? ok, if you say so. You're doing a great job-good luck!

[Ike]

Jakub, Welcome. Nice looking design. I have a feeling that in about ten years you're going to have a lot of old timers worried about their careers.

[timgoz]

Jakub,

Welcome to the forum young sir. It is nice to see a young person with both an interest in, and talent for boats.

Take care.

Tim

[Bergalia]

Welcome to the forum Jakub. That's a handsome piece of work you've produced. And nice to have your company (but candidly you'll find all other members - except you and I) are 'old farts'.
Mind you, now and again they do come up with some good advice.

[marshmat]

Berg, I ain't an old fart yet- gotta get outta school before you can start throwing that term at me

Jakub,

A few comments here from someone who had a similar fervour for all things marine at that age, not so long ago....
- That is a BIG sail plan, especially with the spinnaker out. Meaning it will be darned fast but will also need some very significant righting moment- ie, the ability to move a lot of weight to windward. I imagine a crew of 2-3 would be typical? You might want to compare different ways for the crew to move way out to windward, ie. trapezes or harnesses, so the boat can carry that big sail plan in stronger winds.
- The mainsail looks pretty close to an elliptical shape, thought to be one of the more efficient shapes for that sail.
- The stays and shrouds look pretty elaborate. One of the problems with complex stayed rigs is that there are a lot of fiddly little expensive parts, any one of which will cripple the boat if it fails. The stays also tend to get in the way when you have crew moving around on a boat this size. Have you considered an unstayed, freestanding mast as an alternative option?
- It looks like the kind of boat that when raced against its own kind, would depend not so much on cash input and maximum hi-tech (as VO 70s and other types that tend to sort-of plane do) as it would on quick thinking, smart strategy and tactics. The kind of racing that's fun to watch and challenging to be in.
- Regarding the keel winglets- take a close look at an Airbus 319/320/321 next time you're near the airport. You'll see a similar shape. The actual design of the things usually involves a few tens of thousands of dollars of CFD supercomputer time but the idea is that by preventing flow around the tip from the high-pressure to the low-pressure side, ie. reducing the tip vortex, there is less loss of lift due to tip effects. Thus the foil behaves as if it had a higher aspect ratio, ie. more efficient. In a boat this results in less tendency to slide sideways with the wind, therefore a better speed in the desired direction. So in short the winglets are a good idea from a performance standpoint, but be warned they're hard to build and tend to be easily damaged.
Keep 'em coming!

[kuba_sail]

Just thanks a lot about all of the kind (and positive critic )words. I'm very happy, that my design had given you a lot of good (artistic) experience. Now I' m working on 5 meters LOA boat, polish national class Żagle 500. Soon my design 'll be uploadede into the net!
Watch out! kuba_sail's coming!
Kind Regards
Jakub Batog