Yrvind

Interesting boat. Truly looking like a "yellow submarine"
Now with some more pictures & videos of test sailing.
Sail area looks tiny, will it be able to make way upwind in harsh conditions?
If initial stability is the low end of desired, can it be used for longer passages with reasonable comfort?
Looking forward on updates of further testing and conclusions.

 

It's happenin'!

Tracker http://www.yrvind.com/tracker/

 

Ok - Best of luck to Sven!

Hope he’ll have a safe and pleasant sail.

 

I don't think he'll go all the way in this boat. Seems like he's just testing it. He said recently about this boat that it was just a prototype (talked about not having money for a bigger boat). Maybe he should spend more time on the planning and drawing before he begins to build those tiny tiny TINY boats.

 

Yeah, perhaps he’ll only make it to the canaries, and then cruise over to the West Indies. But as long as he is happy and safe, all good. We’ll see.

 

Yep that's what matters. But now it seems that he isn't going anywhere. Hope he's just testing and nothing is wrong. (Tracker)

 

Mm, his progress first 84 hours is comparable to driftwood. If I remember correctly from his last Atlantic crossing via the canaries he started roughly the same but then found his slow but steady pace eventually. Will be interesting to follow next few weeks

 

Hee hee hee driftwood! Let's hope he's just getting over seasickness and is not hurt or dead, before he continues. Hope someone will know if something is wrong.

 

The sail area is tiny. This boat has an S/D of roughly 5.0, by my estimation. A typical cruising sailboat has an S/D of anywhere from the low teens to the low twenties, with more traditional ones having the lower number and with the more modern ones having the higher one.

Anne Davison's Felicity Anne had an S/D of approximately 8.5 when it was modified for the first attempt at a solo Atlantic crossing by a woman. It made it. For the longest time, that boat probably held the record for low S/D. It was surpassed when Sven crossed the Atlantic with Bris IV , which had an estimated S/D of 7.5.

If he gets anywhere, I believe he will make it to New Zealand. This is because most of the voyage will be down wind and most of it will be in the wind rich Southern Ocean. I do believe, however, he will get a lot of exercise with the yuloh, with 20 mile days not being at all uncommon. The big risk is that he will have to make his transfer from one ocean current to the other in light wind conditions. To do this, he may have to go against an ocean current for some time. And that will take some power to achieve. If he fails, he may find himself trapped in the North Atlantic for maybe weeks, if not indefinitely.

But if he manages, and once he gets a favorable wind with any strength, his boat may surprise us with daily passage miles. He may get a good number of 140 plus mile days. This is because the boat is quite narrow for its length, and so it will be pushing less water out of its way than if it were wider.

Ex Lex has both very high ultimate stability and very shallow draft. This is very hard to achieve, with decent initial stability, without massive amounts of ballast. Such is more commonly done with a deep Keel, a good amount of external Ballast, a moderate Beam, and often with high Sides.

Once shallow Draft is thrown in, the equation gets upset. The initial stability diminishes, as the Beam needs to be made ever narrower in relation to the height of the sides, to get the high ultimate stability. I know because I have tried.

Attached below is a drawing of my Lola 520 design. Originally, it was supposed to have nearly 200 sf of sail and be water ballasted. The water ballast was the first to go because it would have ended up making up almost half the displacement. It was replaced with sand, which is nearly twice as dense. Next, the rig had to be whittled away at. It got shrunk down to just 153 sf, with an estimated S/D of just under 12.0. But, by thunder, I was able to get my high ultimate stability, with a Draft of less than two feet, and a ballast ratio of just under 0.3o.

 

The tracker shows he has the wind behind him so he should be romping along.....

 

Here are two sketches taken from Yrvind's ExLex pdf. They demonstrate how he can move his sails to different positions, to balance the boat in different conditions.

What struck me was how low the sails are. I wondered if the sails would often be blanketed by waves while ExLex was in a trough? If so, it seems that would greatly reduce what must already be a slow pace.

 

I see a straight line!

 

Yes (very) slow and steady progress now.
Mostly in light wind conditions.

 

Past 24 hrs: 38 Mi
Total: 227 Mi
Speed: 0.43 kn
AVG: 1.4 kn

Sorry guys but if he was rowing he'd be going faster than that - wind behind him remember.

 

Tracker: https://www.followmychallenge.com/live/yrvind/, scrolling gives zoom in-out, you can also can click + drag the map there.

The standard setting is wind, when clicking the ‘‘menu’’ button on the left side, then there are different overlay options to choose from, like e.g. waves, currents, etc..

The ‘‘waves’’ option shows wave height, but also the direction of the ocean swell (the regular movement of over long distance traveling rolling waves that don't break), which is something different than the direction of the ocean current.

Judging from the wind and current and swell direction at the time of this posting, I wonder what other boat under 100% sail power would make any progress there, as the wind is near zero.

A bit more to the east it seems a bit better for direct progress, but he wouldn't like to have north and west Spain and Portugal and northwest Africa as a nearby potential lee shore in a maybe later westerly wind for a short time, also it wouldn't be much fun to end up in the Bay of Biscay to begin with, hence his course, I'll guess.

Also in a near calm the boat rolls with the ocean swell when having it abeam, which to me looks like very tiresome in a boat with such a initial tenderness, so at the time of this posting he seems to be heading southwest, right into the swell direction, to have the it on the bow, which also gives him the desired distance of Biscay plus Spain and Portugal, that's if there's any progress at all in these circumstances, maybe he makes his little progress by sculling right now.

More west the wind is from the south, so it would be bad to end up there, so there seems to be little other options than slow progress at this moment, regardless the boat right now.