Could you Make a sailboat completely watertight?

[Arthurgifford]

Originally Posted by jeanathon

You mean like a submarine? Yes, but as Adelie said being inside in a tumble dry mode with broken bones would be no fun. Hamster ball might be better, but I would think vomit might be a problem.

Lol. I got a solution to that! Just cover my body head to toes in layers of bubble wrap and cut a little hole at the mouth to breath! Problem fixed! (Being sarcastic btw haha). Thanks for the comment

[Arthurgifford]

Originally Posted by TrentePieds

MarinR said: "If you start motoring you need to open the air inlet, and then the lifeboat is not completely watertight anymore."


Selbstverständlich :-)! Thot it would be a salutary lesson for the OP to work that out for hisself ;-0)!

TP

Haha yes I figured that. I honestly have no intention of making a boat completely watertight like that, just thought it was an interesting idea. You could probably make some sort of fan that could sense when the boat is right side up and dry that sucks in fresh air but ya it’s unnecessary

[Arthurgifford]

Originally Posted by blubaju

Suggest other way round, take a submarine and add - motorsaileralike, a rig. Once the storm hits you, dive, a few feet below the waves it is calm, use your mast as periscope. To go the way you are thinking is very cumbersome and you are still exposed to the elements

A sailboat that could turn into a submarine?! That would be interesting! Haha

[MicHughV]

Most people that see a wave, don't understand that a wave has two components, one that you can see on the surface, and one that you can't see below the surface...

You'll never see large waves breaking on the beach, as the height of the wave is in direct proportion to the depth of water, as the beach gets shallower, so does the size of the wave......typically, a wave will " break" when the depth of water is less then the height of the wave.

Offshore, there is no beach, as the water is too deep, but the "depth" of the wave is still there, so big waves can and do have a large sub-surface "component" that can roil a sub.

It gets complicated to explain without me drawing diagrams, but you can research this online.

[Fore and Aft]

I have been on a home built steel yacht that could be divided into three watertight compartments. I believe they were submarine style doors that could be properly locked down, same with the companionway. I can't remember much about the boat. The owner made one concession for some heavy duty hatches for light as it was dark down below. The owner proudly told me how much the yacht weighed and you could blow out sails before anything gets damaged.
Cheers

[Knotical]

To the OP - if I understand your question correctly I believe you are looking for a boat that does not take in water in any condition and does not sink, if yes look up Sven Yrvind’s boats.

[MicHughV]

My first boat was a homebuilt steely....it was about as watertight as I could make it....

Some years later, I was in a heck of a storm, and much to my surprise, sea water was coming inside the boat thru' those tiny vent holes on the side of my dorade vents. The actual cowl vents had been removed, and the cowl vent holes covered with a plate...but some pretty big waves were washing across the deck with considerable force, enough to allow a wave thru' that tiny vent hole and up and over the tube that allowed fresh air into the boat..I'm not talking about a drip here...every time a wave hit, not an inconsiderable amount of sea water came pouring in.
There wasn't much I could do about it at the time, except live with it, and clean up the mess after...but I certainly was not expecting sea water intrusion from that quarter...

Even a pinhole will let in a considerable amount of water that's under pressure...a number of holes or other vents, openings, gaps, etc are on a boat. I'm not sure how you'd make a boat completely watertight without considerable effort.

The stuffing box is an area that is often the culprit for water intrusion...but leaky thru' hulls, hoses, etc, are all points of possible leaks.

[StuM]

Don't most US* submarines have "sails" ?
If so, aren't they technically "watertight sailboats" ?


*A lot of other nations have "fins"

[Scorpius]

Earlier someone said a sailboat without a mast would be more stable. It's not. The mast adds inertia and dampens rolling. A monohull sailboat without a mast rolls terribly.

[billgewater]

This is old hat stuff. For thousands of years, people crossed major oceans on sealed water craft. We call them "rafts". So yes, it can be done. And you can set a sail, or install an engine on top.
You can even build a weather shelter on the top. You can make it really wide so the likelihood of a rollover is minimal. Or you can buy an off the beach catamaran - fully sealed hulls - goes like the clappers - tricky to right if tipped over but . . If you want access to the internal space, then clearly an entrance is needed and then theoretically at least, water may enter.
I'm sure we have all heard of some small sealed vessels that have survived all the oceans can toss at them. Message in a bottle.

[hpeer]

To he serious for a moment….

Is it not just good design to create a boat that is pretty darn water tight? Should water tight not be an enviable goal? Is it not good prep and seamanship to be able to close up a boat?

I think it was Vigor who said “think inverted”. What happens when you roll? Pretty sure you want a boat that is close to water tight in that circumstance.

I think our boat is pretty good, but not great, at being water tight. The chain haws pipe is an obvious problem. Our dorades can be closed tight from inside. All brand new blue water class port lights. I have a hole for some wire in a cockpit locker that would let some water in.

My “problem” is the companion way, that would be pretty leaky. Given some time I could stuff it up, should help. That needs work.

[Adelie]

Originally Posted by Scorpius

Earlier someone said a sailboat without a mast would be more stable. It's not. The mast adds inertia and dampens rolling. A monohull sailboat without a mast rolls terribly.

I wrote that:

Originally Posted by Adelie

...

Once the mast is lost the boat will be more “stable” but also more prone to rolling over. Counter-intuitive but true.

You just opened a can of worms.

A boat without a mast is more stable with regards to the technical definition of stability. That is, it has more positive righting moment under the stability curve, a higher peak positive righting moment, a slightly higher Angle of Vanishing Stability and a lower peak of inverted stability.

Higher stability lets you carry more sail are in higher winds before reefing is needed. Stability is only very tenuously related to capsize resistance.


The mast on a boat VASTLY increases the roll moment of inertia for the boat. A mast, which accounts for something 1-3% of the mass of the vessel, is responsible for 1/3 to 1/2 of the roll moment of inertia.

Higher roll moment of inertia means that a boat rolls more slowly when a gust or wave acts on the boat, and the roll stops more slowly once the gust or wave passes. In breaking seas the result is that a boat is much more resistant to capsize.


Wind thru the sails and water flow over the hull dampen rolling. This portion is way more complex than I care to explain, and I'm less sure about the physics.

Comfort is a whole 'nother ball of wax.

[garyfdl]

Originally Posted by StuM

Don't most US* submarines have "sails" ?
If so, aren't they technically "watertight sailboats" ?


*A lot of other nations have "fins"

LOL

The only thing left of my first boat (USS Thomas Jefferson - SSBN 618) is the sail. It's on display in Gosport Park in Norfolk, VA.

I was able to visit 'her' yesterday. (Needs paint.)

[warren5421]

Hy grayed! my first boat was the USS Sam Houston SSBN 609 blue crew. We fell over 300 feet in the North Atlantic, lost all power but the battery. Seen guys I hadn't seen the whole patrol. We took on no water though the air intake was open for the diesel when it started. The COB was on the dive station before he got the chicken switches open we were past the 300 foot mark. Rods were on the bottom, was a fun night.

[AKA-None]

Well don’t they make spacecraft water tight