The Wind Powered Sail-less Boat

[Windmaster]

Originally Posted by ThinAirDesigns

NALSA DDWFTTW ratification reports are now up: www.nalsa.org

And a great article by Kimball Livingston, an editor at Sail Magazine:

http://kimballlivingston.com/?p=3971

Nowhere in the above article or anywhere on the Faster than the Wind website can I see mention of Jack Goodman - a member of the Amateur Yacht Research Society who, with his downwind faster than the wind model (on youtube here: http://www.youtube.com/watch?v=aJpdWHFqHm0) showed that it was possible.

I don't think Jack was the originator of the idea (which has been talked about on AYRS channels for many years) but he was the first to build a model, film it, and demonstrate that it worked.

I am willing to be corrected on this if I have got the timescale wrong, but it seems a shame that in all the ballyhoo, the first demonstrator of this concept should be forgotten and not given any mention.

[ThinAirDesigns]

Originally Posted by Windmaster

Nowhere in the above article or anywhere on the Faster than the Wind website can I see mention of Jack Goodman - a member of the Amateur Yacht Research Society who, with his downwind faster than the wind model (on youtube here: http://www.youtube.com/watch?v=aJpdWHFqHm0) showed that it was possible.

I have no control of the article, but Jack is featured prominently on the faster than the wind website -- check out the very third post:

http://www.fasterthanthewind.org/200...t-hoax_03.html

I don't think Jack was the originator of the idea (which has been talked about on AYRS channels for many years) but he was the first to build a model, film it, and demonstrate that it worked.

You are correct, Jack was not the originator, nor the first to build one (see the very first post on our project blog)

By all accounts so far it was first done in the the '60s by a team of engineers from Douglas Aircraft, but even they weren't the ones who came up with the idea and as they did it to settle a bet between friends, they didn't document their exploits in a way that satisfied very many critics.

AMO Smith (google him), the Supervisor of Aerodynamics Research and Chief Aerodynamics Engineer at Douglas and one of his wind tunnel engineers, Dr. Andrew Bauer discovered the idea in a paper presented by a midwestern student who was was angling for a summer internship.

Unfortunately, no one remembers who the student was (they didn't get the intern position) so credit for the actual invention will apparently remain nebulous for all time.

Bauer believed the student was correct and AMO believed DDWFTTW to be impossible. They made a bet and Bauer assembled a small team, built and sucessfully tested the device. AMO paid off on his bet and by all acounts it was near 40 years before anyone physically tried it again (Goodman).

I am willing to be corrected on this if I have got the timescale wrong, but it seems a shame that in all the ballyhoo, the first demonstrator of this concept should be forgotten and not given any mention.

We give Jack HUGE credit everywhere we go and are in regular phone and email contact with him to this day. Check out the video that we did when we were trying to get this on MythBusters:

http://www.youtube.com/watch?v=_fBDcchw5nw

In history if we are remembered in any way with regard to DDWFTTW, it will be because we truly were the first group who documented it well enough to bring most rational people around. Before us most folks still called Goodman and Bauer crackpots and hoaxers -- now it's only the moonshot denier types who will never be convinced.

JB

[Windmaster]

You're right, you have accorded Jack (and Bauer) some credit.
It was only in the article that Kimball Livingston did not mention it.
He has been in touch with me and points out that he did not have space to go into a complete history of the subject - which is true I suppose.

[jcolvin]

Just jumping in here, I'm a physics BSc, also a glider pilot and sailboat owner. I was ready to call "hoax" when I first saw this, since I just could not visualize how the machine gets energy from the prop when the prop is seeing zero apparent wind. What made it "click" for me (and I don't see anyone else mentioning this, which is weird..perhaps I missed it somewhere in the lengthy thread), is that it is not the turbine driving the wheels but the wheels driving the turbine. When you first see this machine you automatically assume that wind flowing through the turbine drives it (and then the question...how does it work when the machine is going same speed as the wind). But then watch it start from a standstill...the turbine goes in the *opposite* direction that it should if wind were driving the turbine directly (ie, if the turbine was working like a wind-powered generator). Clearly, the wheels are driving the turbine, not the other way round; thanks to the magic of gearing, torque from the wheels is greater than the opposite torque the wind is exerting on the turbine blades. Once I saw this, it became apparent how it could work; before that clicked, I was mighty sure that it was just plain impossible.

bravo!

[Windmaster]

Originally Posted by jcolvin

Just jumping in here, I'm a physics BSc, also a glider pilot and sailboat owner. I was ready to call "hoax" when I first saw this, since I just could not visualize how the machine gets energy from the prop when the prop is seeing zero apparent wind. What made it "click" for me (and I don't see anyone else mentioning this, which is weird..perhaps I missed it somewhere in the lengthy thread), is that it is not the turbine driving the wheels but the wheels driving the turbine. When you first see this machine you automatically assume that wind flowing through the turbine drives it (and then the question...how does it work when the machine is going same speed as the wind). But then watch it start from a standstill...the turbine goes in the *opposite* direction that it should if wind were driving the turbine directly (ie, if the turbine was working like a wind-powered generator). Clearly, the wheels are driving the turbine, not the other way round; thanks to the magic of gearing, torque from the wheels is greater than the opposite torque the wind is exerting on the turbine blades. Once I saw this, it became apparent how it could work; before that clicked, I was mighty sure that it was just plain impossible.

bravo!

That's quite right, so it's really better to describe the "turbine" as a propeller. Lots of people have mentioned it and to those who understand it, it's quite obvious.

[Richard Miller]

Originally Posted by Erwan

Hi Duncan,

Just to suggest you to investigate the propulson efficiency of your underwater device.

As your boat will probably be relatively slow, You will probably need a big propeller in the water with low revolution.

There is an alternative solution for low speed.

Imagine a square/ rectangular box open at the front and back sides, just like a matches-box after pulling out the inside part.
This box is underwater and its open ends are in the direction of the water flow of course.

At about a third of its longitudinal axis you have a connection-rod which transmit a rotative motion (the windwill above the deck) into an alternative motion.

This connecting rod moves a flat plate inside the box, of course you have to adjust the box-thickness with "crank" stroke.

The flat plate moving inside the box will move quite similar to a dolphin tail, and the box will limit tip vortex.

My English is far from perfect, so if it seems confused to you, make a drawing of it, everything will be clear.

Regards

EK

Hi Erwan;
Have you actually tried this? The theorie sounds great. I wonder how well it would work in practice? It's a dolphin's tail in a box. It gives you the large contact with the water that's required for good velosity. See the posts that talk about large propellers in the water. Richard: PS Your English is just fine. I understood everything. PPS: Peter, go to your shop & try this.

[New Dawn Fades]

Hi, I see this thread is now 55 pages long and so I don't want t start a new one.

I have seen it written that a windmill powered prop will run a boat at about half wind speed in any direction, so basically what I'm looking for here is a sort of cost/benefit analysis from those of you who have been following this thread for all these years.

This would be going on an aprox 40' aluminum blue water cat that is yet to be designed.

For example, it sounds like the boat will be slower than one with sails and yet it can sail directly into the wind, so that helps a lot to make up some speed difference.

I assume that a good windmill will cost less than a moderate quality set of sails and that it will last longer and be easier to handle.

Of course there is one great benefit that sails can't provide, and that is mass quantities of electrical power available when you are stopped or drifting. I'm planning on having a mini welding shop on the boat (welder in the hull, welding on deck =) to earn some $$ in remote areas as I understand there is frequently the need for welding and metal fabrication.

[New Dawn Fades]

Originally Posted by Richard Miller

Hi Erwan;
Have you actually tried this? The theorie sounds great. I wonder how well it would work in practice? It's a dolphin's tail in a box. It gives you the large contact with the water that's required for good velosity. See the posts that talk about large propellers in the water. Richard: PS Your English is just fine. I understood everything. PPS: Peter, go to your shop & try this.

Due to my association with aircraft design, instinct tells me you can't come anywhere near the efficiency of a decent prop with any kind of paddle device

[Windmaster]

Originally Posted by New Dawn Fades

Hi, I see this thread is now 55 pages long and so I don't want t start a new one.

I have seen it written that a windmill powered prop will run a boat at about half wind speed in any direction, so basically what I'm looking for here is a sort of cost/benefit analysis from those of you who have been following this thread for all these years.

This would be going on an aprox 40' aluminum blue water cat that is yet to be designed.

For example, it sounds like the boat will be slower than one with sails and yet it can sail directly into the wind, so that helps a lot to make up some speed difference.

I assume that a good windmill will cost less than a moderate quality set of sails and that it will last longer and be easier to handle.

Of course there is one great benefit that sails can't provide, and that is mass quantities of electrical power available when you are stopped or drifting. I'm planning on having a mini welding shop on the boat (welder in the hull, welding on deck =) to earn some $$ in remote areas as I understand there is frequently the need for welding and metal fabrication.

Sounds like a great idea! Go for it!

[New Dawn Fades]

That's very nice, but I'm looking for a cost comparison.

Also, I'm thinking it would be good to have the windmill run a generator/motor to either provide power or run a water prop. The water prop would have an identical generator/motor, that way either one could drive the other one and either could provide electric power.

[Windmaster]

Originally Posted by New Dawn Fades

That's very nice, but I'm looking for a cost comparison.

Also, I'm thinking it would be good to have the windmill run a generator/motor to either provide power or run a water prop. The water prop would have an identical generator/motor, that way either one could drive the other one and either could provide electric power.

That's theoretically sound, but difficult in practice. I've seen a patent about it.

[CaptBill]

Use the power to charge up a flywheel then pull the power off the flywheel. You can power any other devices from the flywheel too so no batteries. Plus the flywheel, mounted optimally, will make an excellent stabilizer

[spork]

The Blackbird has been converted from a downwind cart to an upwind cart. In a couple of weeks we'll be taking a shot at a record going directly UP wind faster than the wind. Stay tuned...