Is my hull shape decent?

Nice for playing chess, but too many square

 

Joseph,

I don't know about software, but from experience I can tell you it is going to be tossed around like a fishing bobber. Assuming it stays on the surface, it will be rolled, tossed, flipped end to end. For a rough aproxamation, take a 1' boat to a water park, throw it in the wave pool, that will be what happens on a reasonable calm day in the south pacific, or north Atlantic. For a bad weather day, throw it in the dryer.

 

This is a guy (kid) that "knows what he's in for" and we'll hopefully read about his safe recovery by a CG someday.

 

LMAO, I can't get my mind off of his first sentence:

"I plant to build a 10 foot luxury yacht capable of handling the open ocean for short coastal cruises."

Any sane person knows there's no such thing as a 10ft luxury yacht. It might make a good luxury life boat though. He's definitely a character.

 

Well, i did further clarify that statement with this:

"By luxury i just meant the best building materials, best paint, best rigging, best electrics, etc etc. The stuff people skimp on to get a bigger boat.

Obviously wont be a luxurious lifestyle but the boat will be a work of art"

Well, I have read just about every book written by people that have crossed oceans in 6'-12' boats

They all describe being put under water by 2 or 3 meters, hearing the boat creak under the water pressure etc etc. None of them mention being pitch poled or rolled every 5 minutes.

A big thing about these journeys is choosing the right route, right time of year and get lucky with the weather.

Serge spent 500 days at sea in a 12 footer on every ocean. Did he get tossed about continuously and end up with whiplash? No.

Speiss, Old swedish dude, and uri the russian crossed the atlantic at ages 46, 62 and 72 in 10-12 foot boats.

Under average sea conditions, its bearable.

In extreme conditions, rig comes down, you stap yourself down with harness, maybe put a helmet on, and ride the rollercoaster.

 

Odd how the people that die at sea never write books about it...

-Tom

 

ROTFL!!!

 

No, but their friends and newspapers do.

Bill Dunlop anybody?

Lost at sea attempting circumnavigation in 10 footer.

 

Seriously I remember a mid-ocean NOAA sensor platform similar to it. It was made of steel with hatches and no window, almost like a submarine. It was wider and squarish, but overall very similar. It was design to wobble around in mid ocean sending hurricane data. I think the discontinued them, they were afraid someone was going to hit them.

 

As an American you should be proud that he is inspired by your greatest ever inventive genius - Wile E. Coyote.

 

What sort of boat was it?

Was it a heavy, full keel cruising type?

Or was it, as I suspect, a light displacement performance oriented boat?

A heavy boat has a much easier motion to it than a lighter boat. It still rolls, pitches, and heaves, to be sure, but at a much slower rate (it sails slower too). (Also, the conditions in the shallow Gulf of Mexico, on a rough day, may actually be more miserable than those on the open ocean, in similar weather, as the waves are likely to be closer together and steeper.)

The point is a smaller boat can be more comfortable than a considerably larger one at sea. A larger light displacement boat reacts much quicker to the sea than a smaller boat with a much greater Heft Factor*. The lighter boat can be stopped by every wave it plows into and can snap roll, pitch and slam in any head sea.

A heavier boat, with a much greater Heft Factor is much more likely to plow into a wave than try to climb over it. It's likely to be wetter on deck due to this fact than the lighter boat. Secure ports and hatches are an absolute necessity for this reason.

You may or may not be able to get used to the constant heaving up and down that would come with anything smaller than an ocean liner. If you can, you should be able to stand the trip.

What is necessary is enough room to lay down and secure places to put your stores and equipment, so they don't get hurled into you and you don't get hurled into them.

Sven Yervin also suggests having a seat belt to keep you from getting tossed about in very bad conditions. Gerry Spies wore a helmet, IIRC.

A ten foot boat should be able to make at least 3 kts in a good wind. The average is more likely to be closer to 2 kts, as there will probably be a number of windless days. Extended calms could be as deadly as storms. An efficient way to move the boat manually should be possible for something this size and would be a good idea.

*A system for comparing a boat's displacement to its Beam rather than to it's Length. A boat can have a low D/L and yet still have a high Heft Factor.

HF= ((B^2)*L)/(20*Displacement Vol.)

 

I think you would be better off with Sharpii’s Bolgeresque design - a lot easier to build and more likely to sail.

 

Sharpi,

It was a J-30. Not the heaviest weather boat around, but far from a light displacement speed demond. I have thousands of sea miles in everything from a carbon fiber 70' racing sled to a San Juan 28' I delivered to Jamaica. I have run bass boats out to the deep water rigs off the Louisiana Coast, and been caught in 100mph micro bursts. Bad weather, and rough conditions aren't a problem, but being caught in bad weather in a small boat is the most miserable experience of my life.

A long thin boat will be much more comfortable in almost all sea states than a short fat boat. Your heft theory just isn't born out by either my experience or the general boating world. Certainly a heavy boat for its size will generally be more stable than a light boat, but short and stubby just means it will be prone to rolling a lot.

Certainly makes me want to go off shore in a boat half this size. http://www.youtube.com/watch?v=1VLiTdN2udY&feature=youtube_gdata_player

 

Unmanned boat in the surf zone?

Like that time the tsnumani flipped an oil tanker

 

Hi, Stumble.

Thanks for the video.

I went ahead and calculated the Heft Factor of a J-30. It is 0.59, which is what I suspected it would be around.

BTW. I posted my HF formula wrong. it is supposed to be:

20*Displ. Vol./((b^2)*L)

Most of the boats you mentioned should have very quick roll periods. The short stubby boat will roll just as much, but will have a deeper, slower roll to it. The long shallow keel also has a dampening effect that shorter, deeper keels lack.

I didn't bother to calculate the HF for a San Juan 28, but, by the picture I saw and the specs, I think I can pretty much assume it's in the same class as a J-30 when it comes to HF.