Is it possible to combine a sailboat, motorboat and submarine?

Hah! so it has already been done. Now the OP can save his money for something more worthwhile.

wonder where they got the sail material, bed sheets? why would you have canvas on a sub? The mast would also be a problem to fabricate it seems to me. Shows ingenuity and determination, I would have attempted the same thing.

 

Burial at sea.

 

But it would not be a covert sub , the white sail sticking out of the water would be a dead give away. And please remember to thoroughly make clear your identity before sailing into New york Harbour in a sub.

 

Portuguese Man-of-War as sailing device

Has anybody analyzed the Portuguese Man-of-War as a sailing device? It has a serious drag chute, partly retractable; the sail is thick, with grooves, low aspect and low CE, partly deflateable; the sail does not rotate and is in line with the hull; ...
several pictures can be found here
From video's like here it is clear that the pointy bow can pivot in all directions.
If the form is perfect to its function what would its locomotion function be in different sea and wind conditions? Can it do more than just being dragged by the wind?
Worth another thread?
Luc

 

As a surfer with experience encountering PMW's, I would say it is in serious need of a depth sounder to keep it out of surf-lines. They tend to cause a lot of suffering when one duck dives beneath a wave only to plant ones face into the underside of a PMW.

 

White flag Frosty or black?

 

Having an inflatable 'sail' might solve the problems of support, not requiring any mast or stays.

When deflated, maybe it could assist with flotation.

"The man-of-war comprises four separate polyps. It gets its name from the uppermost polyp, a gas-filled bladder, or pneumatophore, which sits above the water "

Hey, with a bit of genetic engineering, could we develop biological boats ? Grow the hulls and flotation at sea, instead of building them on land.

 

Hi tahroo,
Anything is 'possible' but review your proposal looking at the costs (not just money), benefits (will it work better than either single function), and answer these points in detail and post the points and summary of the evaluation that you have made...

 

What about a catamaran sub? My brain is fresh this morning so I Got all kinds of ideas just spweing out at the moment till the coffee wears off.

You could have trampoline for the kids in the middle and a theme park on the front bit.

But what a fantastic smuggling boat. you could secure expensive cars on deck then all secret like take them to countries that dont have them.

 

Nothing on the flag though 'eh Frosters...

Wait a minute, there are countrys without cars...?

 

That's it frosty, hide two subs as a giant cruising catamaran. bet you could carry a lot of sail with that too. conditions get rough on the surface you can go down for a bit. rig one of those retracting masts and sails as on Costner's Waterworld multi-hull, and you can go down to avoid the coast guard.

 

There have been multiple threads on this same issue here and at woodenboat.com. The search engines are not very good but you should find them. Sorry if I repeat someones answer, but this is such a bad idea I couldn't read the thread.

 

it just seems so impractical, how would one prevent the sail from being water lodged when submersed? Also seems like a safety hazard, the more complex the vessel the more the chances of something going terribly wrong.

 

Duh - you could take it down and stow it like every other yacht.

Yeah, like the huge superliners of the sky , thousands of people use daily.

Its a project that new technology and science could solve, but most likely wont because sail is such a commercially useless technology.

2/3rds of this project have been solved by every naval submarine in the world - fast powering on the surface, and underneath.

Why you would want to add a sail intrigues me.

 

think of it as a powered surface vessel, than can also submerge, that also has a back up power system to move it when out of fuel.