Unusual design for an extra-heavy-displacement 11ft long Atlantic Proa for circumnavigation

Oh no!

Looks like someone didn't do their weight study and meta center calculations.

Here is a follow up video about it :

That yacht was a cautionary tale of bad management, lack of communication and general poor judgement.
There is likely a thread on it here somewhere.

In this link, if you scroll down to post #19 by @Tad (Tad Roberts), he offers a good analysis of the incident.
Stability rules of thumb? https://www.boatdesign.net/threads/stability-rules-of-thumb.67326/page-2#post-934839

And there is a lot on the NTSB site about the Baaden capsize -
Search https://www.ntsb.gov/Pages/search.aspx#k=baaden%20
 
OK. It looks like this thread is nearing its natural end.

But, just for everyone's amusement and to satisfy my own curriousity, I have sketched, in facet form, a plank-on-edge concept, just to see if I can do it.

(see attachment below)

Granted, most of its 27,000 lb displacement would have to be ballast. But that could be spread out over the expansive flat bottom, so may not have to be lead. The schooner rig was chosen to keep the heavy main mast out of the bow. Besides, this hull form would never be an upwind champ anyway. The mainsail is a ballanced lug, to limit the length of boom going over the lee side. I was just seeing if I could get enough sail area to get the brute to move. I think I have accomplished this. The jib is not calculated in the S/D, as it is intended only to keep the bow pointed downwind. Sailing upwind, it will be furled.

The big question is: will there be enough initial stability to stand up to this sail area?

I think the answer is no. It will heel quite a bit, maybe 20 to 30 degrees, before its weight distribution effectively counter acts the heeling moment of the sails.

I chose the 27,000 lb displacement, because it is close to what the original poster wanted. Notice how much longer it is than the original 11 ft. I originally thought that double that length could be made to work. But some quick math showed me the error of my ways. The damned thing rode just too deep in the water for the ends to lift for the seas. Hopefully, I have sketched in enough buoyance in the ends for them to rise to the bigger waves. The smaller ones, it would tend to sail right through. Hence I tried to keep the fore-deck work limited.

The masts have no shrouds or stays. This is for two reasons:

1.) this boat will roll minimally except for larger waves (when you want it to roll).
2.) There is just not enough staying base to make shrouds worthwhile, unless chainplate guards (to mount them well ouside the hull) and/or a ladder of spreaders are used.

I think this concept comes about as close as possible to meeting the original poster's goals (as incredibly unreasonable as some of them are). Even though it might, maybe be workable, it is a cautionary display of what design compromises must be made to meet a rather extreme design requirement. I don't know why in the world he wanted such a huge displacement. As you all can see, I came up somewhat short of the mark. I think about 40% lighter would nake a much better boat, and meet the same goals (as much as practical).


POE630.png
 
Page --10--

THE END
 
Just thought I would correct myself on my last post were I have a thumbnail of a design concept. It doesn't have anywhere near the S/D the drawing says it has. In fact it has only half of that. How I overlooked such a gross mistake, I will be wondering for a long time. Perhaps I was so keen to see what the boat would look like that I drew a rig that would fit comfortably and never noticed it was half the size it needed to be. And it is exactly half (not including the jib). The correct S/D for the rig drawn is 5.3. I suppose it might sail with that small of a rig. Sven Yrvind got away with an S/D of around 4.0 on his first Ex Lex. But the thing barely moved. He did make port, if I remember correctly.

Still, this is a huge mistak on my part. It kinda makes me glad I'm not doing this for a living.
 
Dear fellow mariners, we are brothers and sisters in this endeavour and I urge you to please treat our brother with respect. He is a bit defensive of his invention, yet is prepared to accept advice around how it can be improved, and most of his negative responses are well provoked by rudeness and unprofessional conduct. Is this how you treat paying clients when they approach you with left-field ideas? Or do you gently guide them towards a workable solution? If you used the rude approach in any business I managed you would be looking elsewhere that day. Are you professionals or high school children?
 
We have a tow line that catches rail junctions, it can get under tension and when it reaches critical mass it will pop free. If your in the bite it can give out some bruises and on occasion a small flight across the deck. Experienced hands will warn new crewman if their standing in the danger zone, unless they don't like them. Then it's school of hard knocks.

What's better, pointing out a phenomenally flawed idea with slightly less than four pages of kid gloves? Or letting the op start burning bead on a floating steel coffin/dead head?
 
We tried subtle and it didn't work.
Many responses on this forum are condescending, pompous, and "subtly" (sometimes not so subtly)insulting, and often completely and utterly unhelpful. Forums like this are for helping people achieve their dreams, not destroying them.
 
Ok, I'll skip the subtly next time. Admittedly not my career paths strong suit.

Nothing like helping someone's dream come true, well unless it's liable to be a nightmare....

Dang there I go being subtle again.

It's a bad idea, unless your goal is aimlessly drifting around the ocean. If your goal is sailing, virtually every other option is superior, except maybe the plastic ball "walk across the ocean guy".
 
"I used to have an extreme prejudice against sailing fast. I am starting to grow out of it." (Sharpii2)

The same thing happened to me. And by posting these types of videos (MiniTransat, Pogo 1) I know I can confuse what I mean.

That is why I often refer again and again to the case of the old merchant seaman retired on a 300 D/L sailboat but able to glide. The sailboat was sailing at 4-5 knots and with the Wave was reaching controlled peaks of 10-12 knots, the wind continued to pick up and it was sailing at 5-6 knots making surfing peaks of 12-14 knots, and at the end it reached 20 knots. The question here is not the speed reached, but that the hull (300 D/L) did it in a natural way as if it were in its element, as the expression "like a fish in water" says.


The Old Man and the Sea - Wikipedia https://en.m.wikipedia.org/wiki/The_Old_Man_and_the_Sea
 
In the video we see the old merchant seaman after a wave hit him, fortunately the cockpit emptied quickly and there we see him putting some order after the chaos.

So I think that a good idea would be a small sailboat that in those circumstances sails at 7.5 knots, so that on the one hand downwind with some more speed "Roll" is minimized and, on the other hand, has a better starting point to go surfing.
 
Screenshot-2023-12-25-16-42-38-79.jpg


The ideal in principle would be that 'Hull Speed' would be 0.60 Froude as that would place the sailboat at the beginning of the 'semi-planing' zone (0.60-0.80) i.e. at the top of the 'semi-displacement' zone (0.40-0.80)

But

But I think a more affordable target would be to aim for a 'Hull Speed' of 0.50 Froude which is a very marked place and that according to the formula given to us by Dave Gerr 'Hull Speed corrected for Displacement' (SLR = 8.26 / (D/L)^0.311) could be reached with 164 D/L which is equal to 1.69 SLR which with 6 meters LWL is 7.5 knots.
 
It seems to me an attainable goal (Plywood) ('young adventurer' mode, she/he, the couple, goes by Airplane)

Sailboat: 1000 kg
1 crew and belongings: 100 kg, fresh water: 60 liters, food: 90 kg. Total: 1.25 Tons, 5.99 meters LWL = 164 D/L
 
It was four pages of fairly diplomatic replies to an idea that was more cartoon than plausible. Makes it hard to accept the notion that we were some how unkind.
We tried subtle and it didn't work.
I wanted to check and read again 57 replies that responded directly to artis' proposal, rather than something else.

By my subjective criteria:
30 posts identified a specific concern. I forgot to count how many of them were related to the core purpose of artis' proposal, which is to reduce motion in a seaway. I am pretty sure it was a minority.
10 posts were some variant of "this is the worst idea ever", only one of which pointed to a specific concern.
8 posts requested more information.
8 posts suggested alternative solutions. I forgot to count how many did only that.
8 posts suggested that seasickness is not a problem worth solving by design. One of them proposed getting a different wife.
5 posts contained personal attacks. 4 of them contained nothing else, 1 of them also declared the design the worst ever. None identified a specific concern. They attracted more Likes than criticism.

Whether that should count as diplomatic on the internet depends on what fora you frequent. I remember nothing that looked subtle to me.

I didn't count how many of the specific concerns artis responded to. I think it was most, it might have been all. He agreed with some objections, he has not abandoned the core idea, but has promised at least two stages of model tests before he decides whether the idea is worth building at full scale. I share the opinion that the model tests will indicate this concept is not worth building at full scale, but I don't get where the notion comes from that artis was totally unresponsive.
What's better, pointing out a phenomenally flawed idea with slightly less than four pages of kid gloves? Or letting the op start burning bead on a floating steel coffin/dead head?
If you want to set this up as a set of discrete choices, then he had four:
1) Declare he had been persuaded to give up on this idea based on arguments alone, without any empirical data.
2) Continue to engage with this thread, despite inevitably diminishing returns because the easily identifiable flaws had been identified early on.
3) Build the first model and get some empirical data.
4) Start welding up the full scale boat.

From what artis wrote in this thread, we can exclude 4), and his absence excludes 2). So either he has given up or he is designing or building a model, or still trying to decide between those two. If the only thing that satisfies is that OP admits the error of his ways, it might still happen if he tests a model and it behaves as we predicted, but that public mea culpa seems less likely the more he is portrayed as ungrateful for not already having admitted his guilt.
 
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