The 1969 Blackbird wind turbine sailing craft concept

[AnssiH]

I'm also really curious to hear, if you already understand how the treadmill version works, and you understand how Galilean transformation works, then you must also understand that that same vehicle design you have in your head for the treadmill vehicle, must also work in the outdoors. Why then do you presume the vehicle designs are any different, and complain about that? Why on earth would they be?

Seems to me you are still just one silly little blunder away from understanding the whole thing completely. Let's find out what that final bit is.

-Anssi

[spartan45]

The Blackbird wind sailing craft concept seems to date from 1969 and like many discoveries from that exciting era left the science world reeling. Here is what I managed to find on the subject. I have posted this on the ‘silly claims’ because 2021 may not be ready for this yet!

It seems from the extract below of The North American Land Sailing Association (full post in ref link) article that after stating land speed record by the ‘Greenbird’ for sail-powered vehicles,  they went on to report  about the wind turbine driven sailing craft, Blackbird, sailing directly into the wind (not tacking), and directly down-wind:

Land Speed Records

The current Landspeed record for sail-powered vehicles was set at Ivanpah Dry Lake in March 2009...126.2 mph (202.9km/h) By Richard Jenkins sailing the Ecotricity Greenbird. Winds were steadily in the 30 mph range with periods nearing 40 mph, which put an end to NALSA course racing for the day.

In an entirely different sort of speed record the, directly into the wind and directly downwind records were set in 2010. Here is the news blurb we posted at the time.

News:
They are at it again! A new record has been set, this time sailing dead upwind...that's right, directly into the wind (not tacking). The NALSA Board of Directors has ratified the following two records achieved by Rick Cavallaro on New Jerusalem Airport near Tracy California on June 16, 2012, with the wind turbine driven sailing craft, Blackbird. Mr. Cavallaro achieved a maximum boat speed to wind speed ratio of 2.1:1 while sailing directly into the wind and a maximum speed in a wind turbine driven sailing craft of 22.9 mph on a different run.
On July 2, 2010 on El Mirage Dry Lake, Blackbird sailed directly down wind at a speed of 27.7 mph in a 10 mph wind to set a first record for the ratio of Boat Speed to true wind speed of 2.8. BlackBird was designed and built by the Thin Air Designs team (Rick Cavallaro and John Borton) and sailed by Rick.

 Ref: https://www.nalsa.org/speedrecord.html

Below is a brief summary I’ve made of The Report supporting World Record Runs in the ‘Dead Downwind Faster Than The Wind’ Category by NALSA; follow the link for the full report:

On 2 July 2010 the ‘DDWFTTW’ craft (powered only by the wind) reached an average speed of 27.665mph at 14:19:16 PDT on El Mirage dry lake. The craft was fitted with an on board GPS receiver and the chase vehicle was fitted with 3 GPS receivers, while average wind speed throughout was only 10mph.   

https://www.nalsa.org/BlackBirdDDWSR/NALSA%20Submision%20report.pdf

Also I thought I’d include an extract from Wikipedia regarding the ‘Dead Downwind Faster ThanThe Wind’ (‘DDWFTTW’) Blackbird craft:

Straight-line vehicles:

Wind-powered vehicle, Blackbird, was designed to go faster than the wind, dead downwind.

Some wind-powered vehicles are built solely to demonstrate a limited principle, e.g. the ability to go upwind or downwind faster than the prevailing windspeed.

In 1969, Andrew Bauer—a wind tunnel engineer for the Douglas Aircraft Company—built and demonstrated a propeller-driven vehicle that could go directly downwind faster than the windspeed, which was recorded in a video. He published the concept in the same year.

In 2006, Jack Goodman published a video of a similar homemade design, describing it as "directly downwind faster than the wind" (DDFTTW). In 2008, Rick Cavallaro—an aerospace engineer and computer technologist—made a toy model based on that design, that fit on a treadmill, and submitted a video of it to the Mythbusters video challenge.

In 2010, Cavallaro built and piloted a wind-driven vehicle, Blackbird, in cooperation with the San Jose State University aviation department in a project sponsored by Google, to demonstrate the feasibility of going directly downwind faster than the wind. He achieved two validated milestones, going both directly downwind and directly upwind faster than the speed of the prevailing wind.

• Downwind—In 2010, Blackbird set the world's first certified record for going directly downwind faster than the wind, using only wind power. The vehicle achieved a dead downwind speed of about 2.8 times the speed of the wind.  In 2011 a streamlined Blackbird reached close to 3 times the speed of wind.
• Upwind—In 2012, Blackbird set the world's first certified record for going directly upwind faster than the wind, using only wind power. The vehicle achieved a dead upwind speed of about 2.1 times the speed of the wind.

Blackbird has been analyzed a number of times since then, in research papers and on the 2013 International Physics Olympiad, and a working toy model was reconstructed w/ 3d-printing instructions in 2021.

Ref: https://en.wikipedia.org/wiki/Wind-powered_vehicle

[ridgerunner]

New guy here (a long time follower of the DDWFTTW brainteaser).

Just curious why this topic is relegated to a "Silly Claims Forum"? Do the moderators on this site actually doubt the validity of the DDWFTTW phenomenon?

Edited December 10, 2021 by ridgerunner

[Spork]

You guys want to claim it's bullshit because you don't understand extremely basic physics?  You want someone to build it?  DONE.  I built it.  I set 4 world records with it.  I've built models of it and demonstrated them on treadmills.  I've posted videos showing people, in detail, how to make their own working models - which many did.  I've written articles on it.  I've given many talks on it at places like NASA and Stanford.  But I'm the crackpot!?  FFS!

Well I'm not going to bother trying to convince people that are fully committed to not understanding basic science.  I might as well try and convince Trumpers that Covid is real or that the Earth is round.  Instead I will offer any takers exactly the same bet Kusenko got.  You want to make $10K the easy way.  I accept in advance.

[OceanBreeze]

3 hours ago, Spork said:

You guys want to claim it's bullshit because you don't understand extremely basic physics?  You want someone to build it?  DONE.  I built it.  I set 4 world records with it.  I've built models of it and demonstrated them on treadmills.  I've posted videos showing people, in detail, how to make their own working models - which many did.  I've written articles on it.  I've given many talks on it at places like NASA and Stanford.  But I'm the crackpot!?  FFS!

Well I'm not going to bother trying to convince people that are fully committed to not understanding basic science.  I might as well try and convince Trumpers that Covid is real or that the Earth is round.  Instead I will offer any takers exactly the same bet Kusenko got.  You want to make $10K the easy way.  I accept in advance.

I guess you are the one we have to blame for all this nonsense, then?

Your one post scores real high on the crackpot index!

Here are just a few index factors, I could include a lot more:

10 points for offering prize money to anyone who proves and/or finds any flaws in your theory.

20 points for defending yourself by bringing up (real or imagined) ridicule accorded to your past theories.

20 points for talking about how great your theory is, but never actually explaining it.

50 points for claiming you have a revolutionary theory but giving no concrete testable predictions.

 

With regards to the last one, why haven’t you tested your car against a neutrally buoyant balloon floating in the wind? Or have you done that and it failed?

What does a treadmill belt and a toy car designed specifically to run on the belt, have to do with your claim? Don’t give me that old Galilean transform Bullshit either. Galileo never had a magic wand that could transform physical objects from one thing into another. All he said was there are different frames of reference for making observations. That does not include transforming a treadmill cart into anything else.

Anyway, I am glad you are not inclined to arguing with this uneducated marine engineer, because I definitely am not inclined to wasting any of my time on you!

 

[OceanBreeze]

10 hours ago, ridgerunner said:

New guy here (a long time follower of the DDWFTTW brainteaser).

Just curious why this topic is relegated to a "Silly Claims Forum"? Do the moderators on this site actually doubt the validity of the DDWFTTW phenomenon?

This is where it belongs

[Spork]

5 hours ago, OceanBreeze said:

I guess you are the one we have to blame for all this nonsense, then?

Your one post scores real high on the crackpot index!

Here are just a few index factors, I could include a lot more:

10 points for offering prize money to anyone who proves and/or finds any flaws in your theory.

20 points for defending yourself by bringing up (real or imagined) ridicule accorded to your past theories.

20 points for talking about how great your theory is, but never actually explaining it.

50 points for claiming you have a revolutionary theory but giving no concrete testable predictions.

 

With regards to the last one, why haven’t you tested your car against a neutrally buoyant balloon floating in the wind? Or have you done that and it failed?

What does a treadmill belt and a toy car designed specifically to run on the belt, have to do with your claim? Don’t give me that old Galilean transform Bullshit either. Galileo never had a magic wand that could transform physical objects from one thing into another. All he said was there are different frames of reference for making observations. That does not include transforming a treadmill cart into anything else.

Anyway, I am glad you are not inclined to arguing with this uneducated marine engineer, because I definitely am not inclined to wasting any of my time on you!

 

It seems you failed to understand my offer...

"Well I'm not going to bother trying to convince people that are fully committed to not understanding basic science.  I might as well try and convince Trumpers that Covid is real or that the Earth is round.  Instead I will offer any takers exactly the same bet Kusenko got.  You want to make $10K the easy way.  I accept in advance."  I've wasted plenty of time arguing with idiots.  If you were confident in your claims, you'd take my money.  I mean you can't be THAT stupid - can you?

 

>> I am glad you are not inclined to arguing with this uneducated marine engineer

Thanks for the disclaimer so I don't expect too much from you.  But you have to admit that not all uneducated marine engineers are idiots.  So that's a poor excuse.

Edited December 11, 2021 by Spork

[ridgerunner]

18 hours ago, OceanBreeze said:

This is where it belongs

I disagree.

I assume that you, a moderator on this "science forum", believe in science and the scientific method?

I assume that you would be willing to read an analysis performed by one of the world's most renowned experts in the field of aerodynamics?

I assume that you have a basic physics background and are able to read and comprehend such an analysis?

I assume that, as a scientist, you have an open mind and would be willing to change your mind if presented irrefutable evidence contrary to your beliefs?

Or are *you* a crackpot, unwilling to even look at or consider evidence that contradicts your strong beliefs?

Please consider taking a look at the two attached analysis (PDFs) written by Mark Drela (of MIT) back in January 2009. (these analyses were originally posted in the third post of this thread)

 

20090101_DRELA_Dead-Downwind_Faster_Than_The_Wind_DDWFTTW_Analysis.pdf 20090102_DRELA_DDWFTTW_Power_Analysis.pdf

[Vmedvil2]

Final Verdict: You are never going to create energy it doesn't matter how you "Gear' it or anything of that nature, energy in a closed system is constant being the Wind and Vehicle , this entire concept is crackpot that somehow you can make "Extra" energy from any known method. The vehicle will have the amount of energy that the wind yields to it which is many orders of magnitude less than the energy of a gallon of gasoline.

"The law of conservation of energy states that energy can neither be created nor destroyed - only converted from one form of energy to another. This means that a system always has the same amount of energy, unless it's added from the outside."

 

There is no debating it, the wind plus vehicle system will always have the same amount of energy at a given velocity of the wind, which is governed by Newtonian mechanics in  the equations already written down by me, the only thing you could do is make the propeller much larger and it would capture more energy from the wind by increasing it's surface area having more wind/air molecules hit it, which is why sailboat sails are so large to capture more energy from the air/wind to make a gallon of gasoline's level of energy they would have to be 1000+ meters^2 depending on the mass of the vehicle being moved by the air/wind.

 

For instance, if you wanted a 2 ton car or 1814.37 kg at 55 mph or 24.5872 meters per second, it would require 548,420.91 joules which at a wind speed of 3.3081 m/s and a air density of 1.225 kg/m^3 for 60 seconds would require a propeller size of 415.254 m^2, which is not really feasible and that is without the effects of friction which will slow you down quite a bit every second so  that is a low estimate on the size you would need to move a car, which 1 gallon of gasoline contains 240 times that amount of energy required to do that or 120 million joules. The zero to 60 mph time on a tesla is 2.07 seconds so to have the same amount of acceleration as a tesla would require propellers that were 12,036.34 meters^2 and this is all the minimum amounts required, so this is really a stupid debate.

 

So unless you wanna power your car with a skyscraper I would stay away from wind powered vehicles, why can't you guys forgo crackpottery and come up with a nuclear powered car or something.

"The fission of 1 g of uranium or plutonium per day liberates about 1 MW. This is the energy equivalent of 3 tons of coal or about 600 gallons of fuel oil per day, which when burned produces approximately 1/4 tonne of carbon dioxide"

Edited December 12, 2021 by VictorMedvil

[Spork]

2 hours ago, VictorMedvil said:

Final Verdict: You are never going to create energy it doesn't matter how you "Gear' it...

Holy Christ you're thick!  Why not maybe respond to something that's actually claimed!?

[Spork]

3 hours ago, ridgerunner said:

I disagree.

 

To be fair, I'm pretty sure they have the "round Earth" stuff in the "silly claims forum" as well.  Consider the source.

[Vmedvil2]

1 hour ago, Spork said:

Holy Christ you're thick!  Why not maybe respond to something that's actually claimed!?

Crank Please.

[Spork]

This really is a "special needs" kind of "science" forum.  I'm just going to assume that's one of those ironic names.

[Vmedvil2]

Just now, Spork said:

This really is a "special needs" kind of "science" forum.  I'm just going to assume that's one of those ironic names.

passing around crackpottery like it's your own dung doesn't make you right, it makes you a crank.

[OceanBreeze]

3 hours ago, Spork said:

To be fair, I'm pretty sure they have the "round Earth" stuff in the "silly claims forum" as well.  Consider the source.

crackpots never fail to interject a round earth comment into the discussion, they just can't help themselves. Just one more confirmation about you.

[OceanBreeze]

7 hours ago, ridgerunner said:

I disagree.

I assume that you, a moderator on this "science forum", believe in science and the scientific method?

I assume that you would be willing to read an analysis performed by one of the world's most renowned experts in the field of aerodynamics?

I assume that you have a basic physics background and are able to read and comprehend such an analysis?

I assume that, as a scientist, you have an open mind and would be willing to change your mind if presented irrefutable evidence contrary to your beliefs?

Or are *you* a crackpot, unwilling to even look at or consider evidence that contradicts your strong beliefs?

Please consider taking a look at the two attached analysis (PDFs) written by Mark Drela (of MIT) back in January 2009. (these analyses were originally posted in the third post of this thread)

 

20090101_DRELA_Dead-Downwind_Faster_Than_The_Wind_DDWFTTW_Analysis.pdf 59.92 kB · 1 download 20090102_DRELA_DDWFTTW_Power_Analysis.pdf 32.82 kB · 1 download

These links don't work for me. But in researching this thing I have come across one analysis by Drela, and I found a few serious flaws in it. For one thing, it was only an argument for a small car that would run on a treadmill. It had nothing at all to do with wind energy!

It is entirely possible to be "one of the world's most renowned experts in the field of aerodynamics", as Drela certainly is, and to also get something else entirely wrong.

You can throw all of those analysis in the trash and settle this argument, that has gone on for at least 10 years (I don't know the full history) by doing the experiment I proposed. Just race this car against a neutrally buoyant balloon that is floating in the wind. That would be soooo convincing, I can't believe it has never even occurred to you people. There must be a damn good reason why it has not been done and I am sure the reason is that you know the car will be shown to never reach wind speed.

Yes, I am a scientist and believe strongly in the scientific method, that is why I propose this experiment.

[ridgerunner]

8 hours ago, OceanBreeze said:

These links don't work for me. ... Yes, I am a scientist and believe strongly in the scientific method ...

Are you saying that you are unable to download/open either of the two PDF files that I attached to my recent post on this thread on your forum?

I am able to successfully click both links in my post and download both of the file attachments just fine.

Please read one or both of these analyses and please point out anything that you disagree with. The longer you cling to your: "I know I'm right and don't even need to look at anything to the contrary" attitude, the more embarrassed you will be once you finally do realize that DDWFTTW does indeed work just as described and does not violate any physical laws. In fact, once you grok how this thing works, you'll see that those same laws dictate that it must work!

You and others claim that the treadmill carts are demonstrating a completely different principle, but on this point you are certainly wrong (See: Galilean invariance). Imagine for a moment that you are standing on the center of the belt of a giant treadmill having belt dimensions a mile wide and ten miles long. (There is also some fog and you can't see anything beyond the belt.) The treadmill is located inside of a HUGE hangar where the air inside is perfectly still. Relative to the Earth, (and the hangar and the air inside the hangar), the treadmill belt is moving along at 10 mph and you are standing "still" on this belt (as you also move along at 10 mph). You also notice/feel that there is a 10mph breeze in you face. While standing still facing into the wind you see a very large, black cart approaching with a 17' spinning propeller coming towards you along the belt traveling in the same direction as the breeze. You marvel, as it passes by going even faster than the "wind", it having a wind streamer mounted above the top of the rotor that is indicating a wind in the opposite direction.

Seriously think about this scenerio for a moment and please re-think your objection to the treadmill being exactly equivalent to a cart traveling outside in a 10mph wind. Here is a video I made where I hovered my RC treadmill cart (that has both steering and a variable pitch prop) for five minutes straight accelerating up and down the treadmill belt at will under complete control.

Once again, I strongly recommend that you read the very well written and illustrated papers by Dr. Drela that I attached to my previous post.

And please lose the infantile You're a crank! attitude. I'm a scientist too (BS Civil Engineering 1981). In fact, back in the 80's and 90's, I actually worked as a rocket scientist! I worked on ICBMs and other solid rocket motor propulsion systems at Hercules Aerospace for more than a decade. That said, Spork (the designer and builder of the Blackbird, having earned both a BS and MS in aero engineering), is much better qualified to educate you - but as you are discovering, he does not suffer fools well (a decade and a half of dealing with close minded deniers just like you does that to some folks!)

Edited December 12, 2021 by ridgerunner
Minor typos, grammer