A future sailboat ?

Hi The Q
It was really fun to check The 3 Rivers Race as I can relate to the feeling of sailing on a river.
When I was young and sailed FD, the Yacht Club was placed on the channel 1000m long to the river and then after while we got to a huge lake.
The funny thing is that is almost the same like sail a Sea Cat at 20 knots on bigger water.
The closeness to the water, when sailing little boat on the river gives the feeling of speed while the tacking was every 60 seconds - nice training!
The closeness to the land is giving a reference for speed feeling - so it is great!
I put my time to check the links you provided - spectacular event. Thank You!
Yes! The Swedish traditional yachts are built to perform well when the top of the sail can catch the wind as very often the small islands are high – no wind at the sea level.
It is, however, a problem even on today's boats as they are overpowered like my Omega 30 and the reefing needs to be done often and I feel that it is too often and too soon.

 

WSW.

I read your piece all the way through.

Wow!

The way you systematically anticipated problems and tried to solve them should be an inspiration to us all.

Your project is intensely well thought out, but there seems to be some gaps in your reasoning.

I'll start with the wing design.

The single wing is best. Adding another wing only increases the total lift by about 20% over the same area with a single wing.

Essentially, you will have a biplane on end.

The further the wings are apart, the better. They can be further apart linearly, further apart laterally, or both. Ancient Chinese junks are thought to have had their masts staggered along the deck, with some on the port side and some on the starboard side. This accomplished two things:

1.) It kept the sail surfaces as far apart as possible, and
2.) It kept the Yards and Boomlets fro fouling on one another. If they were all installed on the center line, the Yards and Boomlets would have had to be shorter.

Another problem I see with your mechanical wing design is top hamper.

Apparently, you want to have a motor on each rib to flip the foil over, when changing tacks. This motor, and its associated gearing is certainly going to add weight, and it's going to do it relatively high up. Not only that, but each rib is going to need an axle that's strong enough to keep both halves in line with one another, in both bending and torsion (as you have well illustrated). This too is going to add weight.

The wing surface itself, with its vertical spline structures is also going to be heavier than ordinary sail cloth.

What this adds up to is a wing sail which is probably much heavier than it needs to be. This raises the CG of your boat, making the moveable ballast (the only ballast it has) less effective when you need it most (when the boat is knocked down by a sudden gust or a big wave)

Now the Chinese Lug (CL), with its many Boomlets, was also a very heavy sail, especially when fully set. But it was reefable (and quite easily so), with the Boomlets and Yard sliding down the mast, and stacking up neatly at the sail base, as the halyard was eased. This accomplished two things:

1.) it lowered the Center of Area (CA), and
2.) it lowered the Center of Gravity (CG) significantly as well.

Both of these happened right at the time when they were most desirable.

Your wing sail has no such virtue. It is either fully up or fully down.

And I can imagine the excitement when folding this thing down during any kind of wind or seaway.

I would suggest going to a symmetrical airfoil and a soft wing surface.

This way, the ribs can be much simpler and a whole lot lighter.

And, like the CL, they can be lowered to reduce the Sail Area (SA) and CG. Being symmetrical, the wing can be made to feather into the wind much more reliably. Not only that, but you could effectively control the wing with just two servos. One would use an internal continuous line to both raise and lower it. The other could sheet it, if the mast is far enough forward for the effective CA to be behind it. Such would cause it to automatically feather into the wind, when the sheet line is slacked.

IMHO, the moveable ballast is nowhere near as redundant as you may think it is. There are two reasons for this:

1.) All the ballast is above the Center of Buoyancy (CB). This means that it is most effective when the boat is sailing level. As the boat heels, it becomes less and less effective. At the same time, the lee deck structure starts to dig in, causing adverse yaw (making the boat turn down wind) at the worst possible moment. Sure, your boat can save itself by quickly feathering the wing, but this will do little good, if the gust is quickly followed by a breaking wave.

2.) Since all the ballast weights are on a single circular track, the ones on the ends can block those between them. So, in reality, you might as well have just two or three weights. Just pray to God nothing jambs the track when they need to be moved.

Back in the earlier days of the long distance single handed ocean races, such as the OSTAR, The Around-Alone, and The Vendee, there was a debate about moveable ballast. How much should be allowed?

They settled on just enough to heel the boat 10 degrees in calm conditions. As you can probably guess, designers took full advantage of this by making very stiff hulls (high initial stability), so more moveable ballast could be used without heeling the boat over the 10 degrees in calm conditions. This later set the stage for canting ballast keels.

I thought of a different solution.

My solution was to stipulate that the moveable ballast not exceed 50% of the fixed ballast (a boat with a 500 kg fixed keel, for example, would be allowed 250 kg of moveable ballast). If such a rule were adapted, canting ballast keels would have been effectively outlawed before they ever appeared.

Such a solution would, IMHO, not be a a bad idea for your proposed boat. Then you would have real redundancy. Because even if the moveable ballast got stuck on the wrong side, the fixed keel could keep the boat from flipping. And, failing that, could certainly aide in righting the boat. With just above the CB moveable ballast, there is no way.

Water ballast would work with such a rule. Half would be allowed to flow to the lee side, just as the boat is to change tacks. The other half would be pumped to the new high side, once the change in tacks was completed. With all moveable ballast, this idea would not work.

I think your ideas have great merit, but don't, IMHO, add up to a really good boat. A major reason I say this, other than the issues I have already brought, is that structural systems are far less likely to fail than mechanical ones, assuming they are both well engineered and well built.

I love the computer controlled, moveable ballast idea and have thought of it for rotating space stations (to create the effect of Earth like gravity). As the astronauts moved along the inside of the outer rim, they would change the space stations CG slightly, causing it to wobble as it rotated. Automated weights on tracks, controlled by a centralized computer, would compensate for this.

 

Hi sharpii2
At last, somebody is writing good stuff – THANKs.
I will need more time to evaluate your suggestions but until then
please note that each Ballast Units is running on own track. Tracks are vertically arranged.
There is an idea to have 2 Ballast Units version (12 totally) on the same track as it will be helpful to “push” (bring) one not working to the inspection window but that is an only by me recorded possibility.

In general, it is a perception issue – this experimental boat is to explore the possibility of doing things differently and see what will be the consequences.
It is not very different from a dinghy or cat – still it will rely on electronics as it is one of the goals.
I know that it is difficult to imagine how a trained neural computer will be able to predict waves and wind gusts and learn how to deal with that in the best manner.
The highly agile, ballast system and wing system, provides the means for advanced control of the boat.

In doing things (kind of stupid) in a very consequent way one can find things which otherwise never will be revealed.

Believe me that I am very aware of all important parameters involved.
Still the best configuration fulfilling as many requirements as possible is:

- 2 rudders in line allowing moving the hull sideways or break the speed almost to stop
This was tested on small motor boat model with el motor – amazing results. These rudders enable to correct the hull direction/position effectively
and in a ways we do not use today.

- 2 wings standing laterally with the ability to adapt camber, thickness, twist and attack angle for
every single wind gust. (sorry that this is so quick that nobody can do it with lines)

- 6 ballast units, each running on an own circular track where electrical energy production is one of the most important goals.

One should not necessary see my boat design as the hard specified, threatening all afloat – it is flexible to adaptations but I am curious about how far we can get on electronics……without compromises and combustible power.

I do like your motto: "I never learned a thing from an argument I won" - me too!

 

Hi WSW, the artwork looks fantastic. I have the same issues that others mentioned, maybe the answers are in your web page that I might have skimmed through too quickly.
Crew movement near rig - killzone?
Stability other than level?

And more:
Why do you want an efficient rig? The boat isn't going to go fast, it needs to consider the system l/d not the rig l/d to get higher upwind angles. And the rig being so puny and small, means all the drags not associated with it is large compared to its lift. So, low system efficiency.


Pardon me for off topic: CT, you asked how to launch a kite. It depends on what kite, what space you have, do you have a stick to hoist it on, do you use helium etc.
What you need is a winch or capstan to let out the lines, and wind.
Some kites are not all that good flying on very short lines, may need to spread out the lines for launch. In super light wind, or with a small platform, such as a E-dinghy it is nice to have a stick to hoist it in, to let it fill without getting wet (foil kites).
Going under bridges: You can steer the kite, so that it is either near the water, or far from it. You can even lay it down and fly it stalled dead down wind just a chord length or less above the water. In any case, compared to lowering a mast, a kite is probably easier to retrieve if the condition makes it necessary.
Guys, have you noticed how on a sailboat, it seems the whole damned thing is filled up with huge, inconvenient stuffs related to sailing? If we were used to kites, and sails on sticks were new, that stuff would be deemed so incredibly ridiculously bizarre, I am sure the idea would be slaughtered here, on a thread spanning several tens of pages with only diatribe and personal insults to boot. Or maybe just laughed at once and left to the archives? 'Anyone who knows me can tell you I am NOT a conservative opposed to new ideas, in fact my father had one when I was younger, and my sister had a medium aged one once, BUT - What, a stick on the kite on top of the deck? To what end? Just to sail heeled? Your idea will never sell. Just move the motor to one side - be quicker, more reliable (doesn't alter heel depending on wind strength)', and FAR cheaper. The loads, the complexity, the inconvenience, the slowness... how will you even make the stick stand up without vertical lift from the kite? How do you plan to steer? Adding another water foil perhaps? Man, this guy...'

 

Best of luck with your project

 

Hi Sigurd
The very first impression is also important – still you can read it more carefully if you want – welcome.
And thank you for coining the “killing zone” – nice, I will use it from now.
I did not record any killing yet but on the model boat, it might be not easy.

The L/D ratio of the wing is substantially improved just by the “killing zone” so I will keep that for now.
For the real boat, I do have a nice solution for that.

The stability is another issue – at least, the boat will not remain upside down.

Note also that this is a development project – not a project to build a specific boat.
Most of the info on my web page is related to a model so the proportionality to the real boat is far from the truth. A big portion of imagination is necessary otherwise one is relating too much to what exists.

The wing is the best wing imaginable – in any conditions the wing can be adjusted for low drag or maximum lift (that depends on boat course) and the hull is not going angled to its travelling direction as most of the boats today. And the underwater appendage is at its minimum (two rudders only).
So the hull gets very low drag as it does not need to be so wide as today's boats.

Different testing methods will be applied to prove that stated already and improve further.
The end results may surprise me as well.

 

See my comments in your text.

 

Hi Sharpii2
Sorry for not being clear in my writing – short thinking...with remains upside down
I meant 180 degrees.
Absolutely correct at it will not recover but it will rather lay on port or starboard maybe 120 degrees depends on hull design.
As the ballast units run as a car on rubber wheels it will slide to the lowest position during turning more than 45 - 50 degrees.
This is a catastrophic situation (“will never happen” – as we people use to say)

However, your comment triggered this what I am best at which is to find exotic solutions to non-existing problems.
If one can imagine that if the wings are still operative after capsize and the tubes where the spars/mast are mounted can rotate. There are too many “IF” but theoretically, it will be possible to recover.
Still, we do have so many scenarios which can lead to capsize that it is not worth to work on it for now.

Lately, I like the word PERCEPTION in relation to how people deal with existing threats.
I remember my first sailing on STAR boat. I was just to sail FD but was invited by an older sailor to sail on his STARE.
From nowhere come a “white squall”. When I was standing on the keel the older guy was watching the distance of the water level to the edge of the cockpit – it was 1-2 inches. We manage the situation and after 5min the boat recover. Same year another STAR sunk when during regatta a quick maneuver in combination with a wave provides enough heeling to fill the boat with water. Nobody was claiming bad design, we like the boat and the fact that it could even get lost was exciting.

Some answers to your previous comments:

“It will be interesting to see if this works. I would think it needs a very predictable wave train. More likely, this Ballast car will simply camp on one section of the track and merely move backwards and forwards a little bit.”

Yes, the Ballast Unit will mostly used as ballast when sailing except during some special circumstances when it can produce some energy as well.
It is mainly meant as ballast but the design goal is to make it maximum efficient as wave energy driven electrical power generator.
Note, that a boat laying on anchor or buoy for a week can produce lot of energy and save it in the batteries. As the batteries become now quickly much better it is a promising approach.
It will not only predict the waves trains but using equations for boat masses and inertia and accelerations to predict consequence. (remember SEGWAY?)

“Think solar panels. They don't slow the boat down, like windmills, generator propellers, and maybe even your moving ballast, and they can be installed on unused parts of the deck and maybe even on the sails “
Yes, the solar panels are not part of the investigation but the boat is WindSolarWaves.
I do not put much effort to deal with that as it is for me simple and existing and ever fast improving technology.

And THANK you for all your inputs!