Direct Upwind Sailing

If that's aimed at me, Montrero, I'll say I'm not particularly sceptical - I just dislike the way some of their fans use dubious methods and statements and arrogant, insulting claims to promote them.

For example, the Peter Worsley chap the OP quotes has been developing such rigs for years but apparently cannot provide any proper proof of the alleged performance - and as we all know, a short video that is edited cannot be called "proof" since any problems can simply be edited out. For example, Worsley has put up a video of his Hawke Surfcat sailing in 2014 that shows no tacks, and also shows it to be quite exceptionally slow compared to the performance of the Hawke with the normal rig. The same applies to his smaller cruising yacht fitted with his rig - it's exceptionally slow. Anyone can make a rig easier to handle if they are prepared to accept dramatically slower speeds.

Worsley comes from the same part of England as the OP and both of them have Hawke Surfcats, a design that came from Australia and isn't very popular in the UK. It would be a very odd coincidence if the OP had no connection with Worsley and yet he referred to him regularly in the third person.

 

I should wrote "you guys are sceptical" . Me too. But sometimes things are not so obvious .

 

This contradicts all your claims of "proven designs" and of researchers that have videos proving the system works.

 

Where I wrote "my claims of proven designs " ?

 

You're dead right, sometimes things are not obvious. But there's arguably a tendency for people pr0moting "alternative" rigs to make overly simplistic and often incorrect claims about "normal" rigs because the "alternative rig" fans claim that the "normal" rigs have obvious faults. For example, Peter Worsley makes several incorrect claims about the "faults" of "normal" wingsails because he fails to realise that they, their operation and their development is not as obvious as he thinks.

We've seen numerous wingsail promoters come here and to other forums and make big claims for the wonders of their rigs. One thing that is very odd is that they seem to have lots of time to make claims, but no time to just go out on the local race course and line up against other craft to gather objective evidence for their claims about performance.

Despite the claims that sailors are conservative, many racing sailors are actually very quick to leap onto proven advances. For example, the modern assymetric came out in the 1984/5 season, I think, and by 1989 we were using them on offshore racer/cruisers. Considering the amount of actual cash, actual work and the compromises in reality (instead of when things are done in dreamer's heads) that represented a very quick adoption of a new concept.

Wingsails are over a century old. I had a friend who had one in about 1974. No one is against them because they are not obvious since we know they work in some applications. Some of us just know that many of the claims made for them are over-hyped and that they do not work in many other applicatios.

 

As a racing sailor, I can claim we always tried to push technology to the limit. Winning justifies adopting a technology; losing discarding it. For example, wingsails can have some advantages, but they also limit rig design, can't be easily reefed or changed at sea, and only seem to be better on a limited range of wind angles. Mylar or Kevlar/carbon fiber sails are the common choice now. Foilers are new fast boats. I can't understand how would anyone call this crowd "conservative".

 

My sailing experience is quiite limited .I'm rather river rat . Theres no gas stations in the middle of the ocean so it's a must consider some sails .
Actually I'm interested in crab claw sails , why I choose kind of cc sail ? They fit my special purposes .Additionally creating some paper models I find out some curious features . I will test some of them by fan .
Why I'm not dig deep into sail evolution and history and competition . Maybe to avoid some sort of contamination . Probably it's wrong term . I try to think up by myself.

 

It is the square wheel syndrome. You don't want to hear about round wheels because your idea is different, therefore everyone else is wrong and foolish. Comparing your ideas to what works in the real world would show your dream idea is wrong. Therefore, you look for excuses to not try it out or compare it to what actually works.

 

Magic. If the cart can exceed wind speed both upwind and downwind then it can exceed the wind speed in still air, which the treadmill seemed to simulate. The blade appears to start rotating just after the thumb comes away from the axle at about 17:55* and before the front (drive) wheels touch down. One might expect that the velocity gradient seen in a light breeze over a stationary surface would be inverted in still air over a moving surface. Note that the model that didn't work had the prop a lot higher off the treadmill than the one that did work. Why bother with a treadmill when there are flat floors to work with? Because a stationary surface generates no wind? Smoke and mirrors.

There is a short video that explains a lot about using YouTube videos as proof of anything. Found it looking for Xyla Foxlin's channel.

At 7:58 in the video, there is a brief view of cat that looks similar to Revelation II. That link says that Revelation was basically a toy that was never intended for serious offshore sailing. Another link shows Revelation II looking like the one in the video along with a number of other windmill boats. The argument over whether it can work on protected waters is not the same as whether it is suitable for offshore passages. Their money, their plaything.

On the other hand, there are others that seem to do the same trick on a larger scale, ROTARY SAILS WIND TURBINE POWERED BOATS CARS AND SAILING SHIPS https://www.change-climate.com/Transport_Land_Sea_Sustainable/Assisted_Ships_Sails_Solar_Projects_Marine_Pollution/Rotary_Sails_Powered_Sailing_Boats_Ships_Turbines_Wind_Cars.htm but I still think there is something unaccounted for. Seems to me that all this says that you should be able to mount a propeller on a Tesla to charge the batteries as you drive. Will anyone here lend me a Tesla and give me about $10,000 to try it out? No? Good thinking.

*If you want to watch a youtube video frame by frame, pause it and then use the comma and period keys to move the video. If the volume changes instead, move the cursor somewhere else after pausing. edited to correct spelling only

 

The problem is not with the square wheel, it is with the flat road. How silly of you not to notice. :>)

 

There is no denying that there is zero energy to tap when the wind velocity and the ground or water velocity are equal. Zero change, zero energy, zero force. However, if one medium is moving against another, that energy can potentially be tapped, and used.

The idea that seems counter intuitive is that movement into the direction of one of those mediums or the other can achieve speeds greater than that difference, but the math, when applied correctly, works. The DDWFTTW vehicle explored in the thread DDWFTTW - Directly Downwind Faster Than The Wind taps into that difference

This is a case where energy generated is in excess of static friction. That difference in excess energy is wholly determined by delta between ground/water and wind movement. That is the limit. No matter the movement of the vehicle, any forward motion is met by an increase in the resistance (kinetic friction) to that motion.

Once one accepts that motion into the wind can be created by the difference of wind and Earth's surfaces, you have to discount any extra energy that might seem to be created by the increase in apparent wind speed. Acceleration is achieved only from the true wind differential, no added force can come from any difference between true wind and apparent wind because the resistive forces rise to match that extra force. Therefore, zero true wind will mean no motion regardless of the movement of the vehicle in an attempt to create a useful apparent wind, while any energy created from the medium differences in motion should be available no matter the direction of motion.

-Will

 

The problem is flat earth .

 

Hi, of course this can be applied and a simpler setup is two VAWT at the stern coupled with voith propellers




With a gearbox to control rpm this can be used for anchoring or leeshore with an engineless sailboat just as alternative propulsion to mount or install when its necessary and keep them stored ready to deploy

 

VAWT+VS isn't easy tusk . Simplicity sometimes goes complictaed .

 

More to the point. This is simplicity, same rotation, same shaft just 2 parts compared to fossil or electric engines with hundreds of faulty components