I don't understand how this car works.

DNFTT!

BillRM


And it won't make one whit of difference to you when it does.

JB

Correct. Full stop.

Despite being nearly illiterate, he does understand some scientific concepts; but he seems to lack the ability (or willingness) to supplement what he already knows with new information. His inability to think outside of the box is punctuated by his unwillingness to try.

I think the problem people are having "getting" this particular solution is the false dilemma of perpetual motion (energy from nowhere.) This machine accomplishes no such thing. If we take friction out, for understanding's sake, it's really just a series of simple machines, with basic equations.

If the normal "sail" area of that prop operates at 50% efficiency (arbitrary guess); then let's observe the twin purposes of the prop (it acts as a sail, and a propeller.) The problem with a standard sail, is obviously that as the vehicle approaches wind speed; the propulsion becomes negligible, so catching more wind wouldn't really do any good. Now consider that a fixed windmill with a 10 times larger "sail" area would be able to harness 10 times the power. In order to counteract the acceleration problem with the fixed sail; the propeller version takes, say, 1/3 of the wind's power and converts it to power that blows directly back at the wind. Now if the entire apparatus operates at 50% efficiency; you still have well more than doubled your effective propulsion.

Once conceived, all the engineers had to work out was the proper ratios.
They now could indeed increase the sail performance by a factor of 10 times between the relative sail area AND the propulsion they converted from the wheels (minus friction of course.) Providing they could build an apparatus they could safely operate; the ability to exceed wind speed is a mathematical certainty.

Basically, just a slightly more complicated than the simple machine pulley example I drew above. BillRM won’t get it, because BillRM doesn’t want to get it. As is his norm, he’ll continue to forward red herring after red herring while boldly calling others fools as he remains blissfully ignorant of the fact that he’s again displaying his ignorance.

My apologies for not reading back sooner, to see you had already explained everything sufficiently. Frankly, I think I enjoyed the challenge of getting there on my own anyway, but I do want to thank you for showing up and explaining everything as well as welcome you to A2K. As you've seen; we have some fine minds as well as BillRM to offer. Stick around!

No apologies needed.

I agree -- the percentage of folks here who approached this with an open mind speaks well of the group.

Thanks.
JB

Bill Occom who does not believe we had landed on the moon is now supporting a group that do not believe in Newton laws how cute.

Second it take real guts indeed to march into a website as a group trying to promote what is likely to be a hoax and call a member of that website who been here for a year a troll!!!!!!

The more of this strong arm tactic that is used here the more I become convince that there is zero merit behind their claims.

Not only are the laws of Newtons indicating this but the laws of human nature is also.

You guys really really wish to sell this on the net.

If they can sell you this nonsense maybe they can sell you on the truth that we landed on the moon.

And yet he hit the nail directly on the head. Are you upset that he didn't call you a quasi-newbie and a troll?

I am unpersuaded by the various putdowns regarding Bill's skepticism.

I had talked myself into believing this story while under the impression that the propeller, like the mainsail on a yacht could be trained at various angles relative to the forward axis of the vehicle. (A rotor can act as a sail or wing as in an autogyro aircraft, but it needs controllable angle of attack (relative to the incoming airstream) to function.

Now I have the impression that the rotor axis is fixed relative to the vehicle axis, and that the pitch of the blades is fixed and not controllable as in an aircraft.. Is this true ... on both counts? I also understand that there is no transmission or clutch between the rotor and the wheels driving (or being driven by) it. Is this also true? All this makes me skeptical.

Another question, is it claimed that the vehicle can attain steady speeds, over level ground, greater than the wind speed, or is the claimed greater speed merely a transient thing resulting from the conversion of stored energy in the rotor?

I don't have a problem with Bill's skepticism; his problem is that the skills on which it is based are not sufficient to discern the facts either way. "A man's got to know his limitations." Clint Eastwood/Harry Callahan, Magnum Force.

Anyway, check out YouTube and search for DDWFTTW.

They are all variations on the same thing to address different concerns, but these are my favorites:

http://www.youtube.com/watch?v=oTMRviy-5zY

http://www.youtube.com/watch?v=dgHBDESd38M

If you understand the equivalence of inertial reference frames (Galilean Transformations) that should seal it, assuming the videos are not faked, and push you to pursue it from there.

The next stop probably depends whether you believe a fixed sail craft can make Vmg to leeward greater than the true windspeed.

[JB should confirm or correct the following:]

The current full-size cart does have variable pitch blades but they are not necessary. The transmission has a ratchet i.e. an overrunning clutch but it also is not necessary.

I am guessing you anticipate troubles moving from a cart speed less than windspeed to a cart speed greater than windspeed. It turns out that with the right blade pitch the bluff body wind forces at speeds below windspeed you don't need variable pitch, but it helps some and of course it helps optimizing the maximum speed.

Yes, steady state and moving directly downwind are part of the design goals, which have been met.

The rotor axis does not change relative to the cart body. However, neither does the true wind direction: the cart is designed to only go Directly DownWind Faster Than The Wind (DDWFTTW).

>>"I am unpersuaded by the various putdowns regarding Bill's skepticism."
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No one has used any putdowns because of skepticism. We invite genuine skepticism. We tire however of deniers that cannot accept even the possibility based only on their intuition - which they insist on substituting for actual physics while calling us fools and hoaxters (and accusing US of hand waving).
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>>"A rotor can act as a sail or wing as in an autogyro aircraft, but it needs controllable angle of attack (relative to the incoming airstream) to function."
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It's definitely not necessary for an autogyro to have collective pitch (i.e. variable angle of attack).
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"Now I have the impression that the rotor axis is fixed relative to the vehicle axis, and that the pitch of the blades is fixed and not controllable as in an aircraft.. Is this true ..."
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The axis is fixed. The pitch used to be fixed, and the cart worked just fine that way. It would even self-start just fine in a tailwind. We've since added variable pitch to give it better acceleration below windspeed.
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>>" I also understand that there is no transmission or clutch between the rotor and the wheels driving"
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There are only ratchets which allow the prop to freewheel when the brakes are applied.
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>>"All this makes me skeptical."
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Fair enough, but it works just fine. Look at the 6 oz models we operate on the treadmills in sir click's links.
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>>" is it claimed that the vehicle can attain steady speeds, over level ground, greater than the wind speed."
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That is what is claimed and has been demonstrated on video and to many audiences, including the Stanford Aero dept, the SJSU Aero dept, the St. Francis Yacht Club, the North American Land Sailiing Association, and the world land sailing speed record holder (who started out even more skeptical than you).

Take a look at this simple machine George:

Obviously an accomplished sailor like yourself can see that this strategy would work. All that's left to imagine is that instead of tying that top rope off to pull at double speed (by tying off the bottom rope): you instead turned an airplane propellor into the wind, driving it with a fraction of the pushing power of the prevailing wind. Want to go faster still? Increase the diameter of the prop... which would have the twin effects of increasing the size of your "sail" while simultaneously increasing the thrust back into it. As long as you gear it so that the "sail" effect is greater than the strain to turn the prop; your speed should increase until wind resistance and other frictions and other power losses max you out (or your instinct for self preservation makes you hit the brakes.)

These are the forces that are acting against each other; not wind hitting the car itself.

The seeming logical leap is that you accept the fact that sails can only use so much of the wind's power, before a larger sail will gain you nothing. What this configuration does, is provide a second way to harness the wind's power in the same space (by pushing back), and thereby allows you to consume more of the wind's power via the previously useless "bigger sail". Unlike the fixed sail; more wind=greater power, which in turn means greater speed.

(Please correct me if I got this wrong guys.)

>>"Please correct me if I got this wrong guys."
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You got a lot of it right - most notably the conclusion that it does work : )

There are two sort of corrections if I may... First there really is no issue of the thrust pushing against a tailwind per se. The vehicle is operating in a moving airmass. The prop works just exactly like a prop in any other airmass. Consider a Cessna flying upwind or downwind. Without seeing the ground there's no way to tell the difference. Everything that happens with the prop and the airflow through and around it are identical in both cases.

The other issue is that of the base of the windmill extracting wind energy. Energy is a weird quantity, but in the frame of the ground the base of the windmill doesn't take or give any energy to or from the wind - because it's not moving.

With this cart the secret (from an energy point of view) is simply that the prop is acting on the air while the ground is acting on the wheels. The ground is going by faster than the air is (because of the tailwind), so you get more energy from the ground in 1 second than you need at the prop in that same 1 second. Energy or work is force x distance. More distance (over the road) takes less force. Just like a lever - a little force times a lot of distance on one end, with less force and more distance on the other. In the end the whole thing can be done with no magic. : )

LOL energy is a weird quantity indeed F*D-1/2MV^2-MGH-volts*amps and if anyone who might wish to have some fun look up how others had explained the working of their perpetual motion machines or the Dean Drive and similar such devices over the last few hundred years.

Then compare those gentlemen words to Mr. Sport statements and others on the Blackbird team.

After you have done so you can then take note how the supporters are spending many many man-hours trying to silent people like me all over the net who are of the opinion that this is highly likely to be another such device.

Yes indeed, I could be wrong however if this device is for real and in the not so distance future more and more evidences will begin to come in why spend the time mounting one hell of a costly, in terms of time at least, campaign to silent questioners ?

When ask what it would take to lay all my questions to rest my reply is first I like to see the NALSA report and hopefully they will also make available the raw data and second I would like to see a completely independent group build such a device and get similar results.

The first part should be available within a few months at the very worst and the second part the building by others of such a device/craft within six months to a year at a guess so why the need for this campaign?

Well, there may be hope for him yet.

>>"take note how the supporters are spending many many man-hours trying to silent people like me all over the net"
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Really - exactly how are we trying to "silent" people like you? Simply by shaming you by pointing out your idiotic statemtents?
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>>"why spend the time mounting one hell of a costly, in terms of time at least, campaign to silent questioners ?"
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Again, rather than making baseless assertions, how about backing one up for the first time ever. How do you think we're trying to "silent" questioners (and by the way, you're not a "questioner" - you're a "denier" - there's a difference).
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>>"I would like to see a completely independent group build such a device and get similar results."
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The ONLY way to satisfy that requirement is for YOU to build one. If anyone else builds it, they will simply be a part of the grand conspiracy. So how about it. Let's see that cart of yours in the next 6 months - or are you part of the conspiracy? I eagerly await your results. Can we follow your progress on your blog as you could with ours? Or will you refuse to build one?

By the way, Spork had you talk Dr. Dan Kammen a Noble prize holding physicist or Dr. Rhett Allain that your wind car does not indeed break the laws of nature?

I love the approach if you were just not so dumb you would see the simple equations on how this work and yet holders of a Noble prize seem to be as dumb as myself!!!

So all you people on this thread who had ended up yielding to a lot of social engineering and pressure and who then announced that you had seen the light might wish to revisit the issue.