Cross Indian ocean in 4 meters dinghy sailboat

We are not entering technical aspects because you are not capable of understanding them. Your proposal for a balasted trimaran shows that you don't understand the basics. Please don't get me wrong, I am not against your dream. You can learn how to sail and gather experience very quickly, but it takes a lot of time to become a capable boat designer. It will take a few years of university level studying before you can do that. Building a boat is easy, regardless of construction method. Designing a good and safe boat for such an extreme adventure is not. In fact I dare to say you will not find many professionals willing to take on your project. So if you want to go to sea quickly you either build an existing design, or pay someone for a custom one. If you want to be able to design the boat yourself it's no problem, open a thread like "what must I learn to be a boat designer and how do I do it".

 

I wont argue, however i could tell you that i have a ready, tested in scale model system for self-righting in "trimarans" as you calling it, yet outriggers for me as i am referring to a far different design than a trimaran. Will be sad for the professionals that haven't reach such a result (some they had with ifs) after all and a random individual does. Definitely i ll agree that boat design need variety of qualities.

If we not entering technical aspects because you think that someone is not capable of understanding but you do, and i do not get you wrong, you will never be able to be open to new possibilities and see far. Im not someone that woke up and thought oh lets build a boat. As a person of skill in some field, i can tell you that i had never think of whats the capabilities of somebody. I have met a lot of people that they only needed a push and put confidence on them and later on they did magic. If professionals think the way you describe, i think they are not professionals and they could not be pioneers beside designing behind somebody's work. As a professional myself in some other field, i do not and i cannot think in such unprofessional way.

Yet for self-righting is something i do not even bother to talk further as i consider it as solved issue.

My comment is clearly not a personal comment against you or about you, but is a very clear message. Are we going to debate in words or are we gonna do anything useful, for us to learn, and yes if you are professional you can always learn to, and of course for others to see too. Definitely im not here to debate words and theories of none, but i prefer to get into a serious talk on the point of each issue. That's productive.

In your last recommendation of a title "what must I learn to be a boat designer and how do I do it". You have to understand that i have no will of becoming a "boat designer" except designer of my own boat which does not make me a boat designer. How do i do it, i have a very clear idea of how to, yet im here asking and collecting information on how to, and further parameters. Yet if i want to be a boat designer to make it as a job i will go to a university course, but im not going to a university just to build my own boat.

 

I will try to stay technical to please you. If your outriggers are low volume enough to be overpowered by the keel ballast in the event of a rollover then their contribution to stability is psychological. In the overall ecuation they are harmfull, because they add unwanted mass (not only the outriggers but the crossbeams also that must be strong enough not to break and the connecting structure to the hull). For the same amount of weight would be better to just widen or deepen the central hull, that way you gain displacement and if you go wide also form stability.

What other technical aspects do you want to discuss? G forces are a issue only for high speed sailing. If you are concerned about waves tossing the boat around you should be more concerned about not breaking bones and heavy weather sailing strategies. If it comes to the washing mashine scenario either the boat breakes or you break.

 

While the self righting is not an issue, the outriggers are there to mimic a wider hull and not a trimaran, are placed on such position. You have to remember that we are talking for a small compact boat, yet the design it is of a deepen hull. The concern it is on the outriggers attached on the boat, for this reason i was thinking of a central frame made by steel, where mast and keel will be hanging on. That way it could take the pressure for a hard weather scenario, but indeed im not sure, im not worrying if that frame will keep the outriggers and the rest, but what if this as whole attached on the central frame of the boat do not handle the pressure at that part. It is a small compact boat but the sea and nature is very strong either. As for bad weather there will be a place to keep you safe from hitting your head or breaking your bones, is something that is solved, as long as the boat does not break. Acceleration is something i haven't think of and i would like to know, why not? Might there can be a solution (which i do not think of). The washing machine scenario is one im concern as i was thinking thinner plywood on the top (while i was concerning about the waves that will hit when there is a stormy weather). So it is possible that rolling in a stormy weather can take the boat apart? Do you have anything to suggest to prevent this?

Technical aspects im very interested at, even i seen lots of videos, it is the right way to build a strong plywood hull that can handle bad weather. Especially the joints. Thickness, layers etc. The hull im thinking of it want be a bottom and then your living space. Between the "cabin" and the outer hull it will be a layer, so in case that a part of the hull breaks the interior will stay intact yet it depends on the damage.

 

What do people normally do when a boat is holed? Is there an inner layer or does the boat just fill up with water? The normal way to do things is to let the boat sink and take to the life raft if you can't stop the flood. Damage of that kind is most likely at the bow and is caused by collisions, so if you have a bow compartment that can be sealed off, that will prevent sinking in many cases. Waves in a storm should not be smashing through your hull, so you shouldn't be relying on an inner layer to stand up to them if the outer one breaks. The double layer approach won't guarantee that both won't be holed in one go either, so it may not provide the safety you think it will, and it won't allow you to make the outer layer significantly weaker, so you're going to be adding a lot of extra weight, possibly for no gain.

The size of your boat is that of a dinghy, so carrying a life raft won't be convenient. What I'd do is design a boat with lots of buoyancy in it like a dinghy so that it can't sink even if holed, and buoyancy bags would be particularly good for parts of this as they'd be more comfortable to be thrown against. Fill in most or all of the space below the waterline with such buoyancy. The boat and life raft then become one and the same thing and you can be safer than you would be in a normal yacht.

An outrigger that's only there to make the hull a bit wider is just extra drag in return for a reduction in cabin space, so make the hull wider instead. If you really want an outrigger, put it further out where it's potentially more useful, but even then ,you could manage with only one of them and sail the boat backwards on one tack, while your keel would still right the boat automatically. Not having the outrigger or not having the keel would likely be faster, but having both may lead to superior comfort and safety, so it may not be a bad idea. There is always room for you to design something better than anything that's on the market today, so it's worth exploring ideas (and sharing them here), not least because most of them have probably been thought of before (and either abandoned for very good reasons or developed further). Keep thinking, but don't be too quick to start building anything - you'll find that you keep having better ideas and need to throw away what you've already built to start again.

 

How about studying the successes and failures for capsules with riders that have gone over Niagara Falls? That might give some insight on surviving leaks and g shock effects that might be incorporated into your boat build. At least some of the survival success will depend on your personal luck, as a few people have gone over Niagara without anything and survived....

https://www.quora.com/If-I-want-to-...rantee-that-I-survive-the-fall-and-dont-drown

PS: The "outriggers" could be made to surround the boat on the outside to be deployed quickly if they were inflatable for dangerous situations. They wouldn't take up any inside room, they would increase buoyancy and maybe could absorb some shock, then possibly could be collapsed to be out of the way for efficient travel- when danger is over. Sorry, just dreaming- I know this is too complex and expensive.

PC

 

Is 4m length a really important requirement ?????. Allowing for 1 person + supplies + food + water + tools + etc. you might be squeezing a quart into a pint. Some of those 'boats' illustrated have the proportions (and possibly sailing characteristics) of a buoy. If you are willing to go bigger (6m) it could work better.... as John Guzzwell did in "Trekka" about 60 years ago.

 

I don't really know how to say this more clearly. It is not that you are not able to comprehend something, you do not know what you need to comprehend. I am sure you are able to learn and understand the concepts needed to design a boat, but you do not know what concepts you need to learn about.

The boat you are trying to design is limited in lenght and also displacement. That means that after you substract the weight of the crew (yourself) and all the supplies and equipement needed, you are left with a certain amount of weight to play with to build the boat. In order for the boat to sail well it must have a certain form. You have three basic options: narrow and deep, shallow and wide, and finally multihull. Then you calculate the structure in your chosen materials to take the expected loads and add the safety factors you think are appropiate, so that you can carry all you need and the boat still sails as expected.
The hull form you choose has implications about how much the boat can weigh loaded, and how it will sail under certain conditions. It also dictates the best strategies to use at different wind strenght. All boats are a compromise, so you must define what is acceptable to you. Do you prioritize speed, safety, comfort, cost, etc.
At this point in your education you do not have the appropiate information to make those decisions. What do you think using outriggers on a narrow deep hull in order to mimic a wider one will bring you? How does that translate into form and weight stability, righting moment, buoyancy distribution at certain angles, etc. How will it sail in the prevailing conditions of yor voyage?

Yes a boat can be destroyed by big enough waves. All boats are engineered to withstand the common conditions they are expected to meet plus a safety factor. You can not engineer "unbreakable" and still expect the boat to sail well, especially in small boats. A rubber ball is unbreakable but does not sail well. Inflatable boats are almost unbreakable and can be made to sail, but if something cuts them it's bad. Every material has its advantages and problems. It is the job of the designer to make the best out of it, and the job of the sailor to see that operating conditions are met (that means applying the appropiate tactics while sailing). Most boats can usually take more abuse than the sailor can.
I really recomend you to read some books about boat design. Preferably in a language you understand very well so you avoid confusion. Start with books aimed at beginners that explain the concepts without asuming prior knowledge.

 

@David Cooper i think you are very right, that concept of layering it could add only extra unnecessary weight for non workable reason, something to consider, yet keeping sealed compartments is an objective, i want the boat to float no matter what. The idea is the dinghy like sailboat to be the life raft itself as you mention. Agree that outriggers and keel will bring more drag and the things related to the hull as you said. I want stability and safety, so the keel is vital for safety i believe. In a small boat outriggers could be drag but stability too, otherwise boat's motion will be high. I like what you say with the idea of one outrigger further out, would be really more useful. Actually i find your comment very useful for me to re-think few things again. Im not sure if i should start working on something or it will be waste, indeed ideas are coming all the time, but i should set a point in time to start building also, that way can learn also how the boat really behave beside the scale models.

@portacruise nice idea, worthy to check it out either it comes in use or not.

@JSL no, 4 meters is not an important requirement but im targeting on a small boat. i already revise my thoughts for a 5.5 meters, i find 4 meters not that sustainable. The reason im targeting or a small boat, is because i like and because i can build it responsibly i believe. Bigger boats need x times more work and techniques that it would take time to master and i can end up spending much more money with no good results. Im not expecting a perfect result by first time, but im going for a perfect result by first time, as David Cooper mentioned there are always things we learn or improvements we want to do. So building small boats, in case of a defect, the costs will be significant lower. Im saying "sail across indian ocean in a 4m dinghy sailboat" but im not going to do it if the boat is not safe. So it is a target and something to look at when building this boat. I want to build it with such criteria, and if comes out a good design, test it, then i ll definitely do it. Here we are to share information, we might fail we might not, but as long as we like it as a hobby or interest, worthy spending the time such way in my very opinion. Surely we hope for something

@Rumars You could be right, might i do not know what i need to comprehend and here i am asking. I believe is the best thing to do. Im not going to make any money out of it, and not going to replace a job of somebody else. There are people who have the money, they like the style, they pay and then buy, and that's right. But there are also other people who like few things and they like to do it just because they like. Many of the things you said and thank you, i have thought about it. Most of what you said are right and agree with you, however this is not the only way. Indeed i understand the right way the tested way, i understand the roles of a designer and a sailor, and none of those. I take your opinion actually very serious. Either way, im gonna make it either it will failed or not. You could help or warn me for the actual dangers. Indeed im not expecting the boat to do everything, but could try the best out of it. Might some good result could come out.

 

Build a 3.6m (12’) dinghy and go out sailing.

My earlier quoted text talked about worrying over looks and it seems that as you are not doing that you overlooked the rest.
You are looking for overly exotic solutions (deployable outriggers, dual skin, deck over living space in < 20’ boat) - solutions that nodoby does. You insist on venturing to these without 1st understatending why current designs are what they are.

Yes plywood can make a strong boat. Obviously. It is one of the most used home built boat solutions.

Read “nature of boats”. It is a good 1st book on boat design.

edit: clarity

 

Nauticals, yes there is another way to design a reasonable boat, and that is by experience. You lack that also, so that is a way that you can not take. You seem to think there is a third way, one of complete innovation without prior knowledge of any kind.

Let me ask you a question. Would you design your own aeroplane only because you can fold a piece of paper and trow it across the room and have flown a few times in a commercial plane and know it has engines and wings? Because that's what you are trying to do, only with boats.

 

I think better analogy would be that a person chooses to build a home built aircraft but insists on
a) using own design with tons of "innovation"
b) does not get deeply familiar on how others do their home-built aircraft and what the solutions there are
c) wants to do all this before a single seat hour on a small aircraft

Nauticals, nobody is saying that you don't have the wits or tenacity to cross an ocean. The odds are against you as I am sure far more many decide on such a goal than actually achieve it - let alone in self-made craft. But it can be done and nobody is telling you not to pursuit that goal. It is a worthwhile goal and I assume that the path can be a huge learning experience and great fun.

That being said I will use another analogy. I don't think there are ANY successful mountaineers conquering the big ones (Denali, Aconcagua, Everest etc.) who wouldn't enjoy small mountains too and who wouldn't start from simple outdoors and hiking and slowly learn the skills and ENJOY all (at least most of) the steps before getting solid enough skills to do the big ones. I have a friend who has been to a lot of mountains. Not sure if he will ever go to Everest but he certainly might. He lives in California and goes to Sierras almost every weekend. He did that long before he started to go on actual mountaineering trips.
Get a small boat (I wouldn't build - let alone design the 1st boat). Used ones are far cheaper than any home built one ever can be. Get in the water.

Being "kind of bad weather" in motor boat is not comparable to being alone in the center of an Ocean weeks from shore in a storm that does not go away.

 

an update:
not sure what the situation is right now but pirates are another factor to be aware of.

 

I don't think there will be enough room for pirates to board.

 

Somali pirates used to take Indian Ocean cruisers as hostages and brought them often to Eyl, and then hold them there till ransom was paid, if worth no money then some were hold as slaves . .

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Locally it seems to be better now . . .

Organized Crime and Corruption Reporting Project - ---> - Behind the Demise of Somali Pirates - Jan 09, 2013 - - - - - - (spare link)

Internet Archive - ---> - The Wayback Machine - ---> - Garowe Online - Somalia: Nugaal governor reach Eyl, meets residents - Apr 3, 2010