I don't understand how this car works.

but no scientific body seems to deal with it ???
just curious ... ...

When some hoaxers are claiming to had broken newton's laws I get very closed mind indeed.

And now that we agree that an ice boat can not move faster then the wind down wind would you care to drop that subject and give the math as how this hoax car can travel down wind at a vel. greater then the wind driving it!!!!!!!!!!!!

Bill is saying that there's a difference between "speed" and "velocity". Speed is how fast you move in any direction. Velocity is how fast you move in a particular direction.

An iceboat's speed can be faster than the wind, but only when moving across the wind. But point the iceboat downwind, the speed drops off, and it can never average a speed downwind faster than the wind itself.

These folks are claiming that the car can go downwind indefinitely at 2.85x the speed of the wind. I'm not seeing where the energy to do so is coming from.

have googled extensively bu t could not find a university nor research organization tackling this - not even science magazine seems to have touched it .

Ice boats can travel faster then the speed of the wind at an angle so there are still wind forces in relationship to the boat.

No repeat no ice boat can travel directly down wind at a speed greater then the wind powering it. No ice boat can travel faster in a direction then the wind component vector in that direction.

You not understanding this is a big red sign on the limit of your education on this subject.

By the way had you ever in your life taken a college level course in physcis?

OK, it's either a hoax or an appalling measurement error (I vote hoax).

OK, it's either a hoax or an appalling measurement error (I vote hoax).

Here's why, and how they got those pictures:

First, can we agree that if there is no wind, and the car is at rest with relation to the ground, that the thing will not accelerate? No forces acting on it at all.

Next, can we agree that the best outcome possible is for the drag from the wheels to exactly match the thrust from the propeller? Ignoring all friction losses, with perfect power transfer, drag = thrust.

It is empirically known that yachts or sailing boats can continuously travel diagonally with (as well as against) the wind at speeds (such that even the component of their velocity in the direction of the wind is) significantly faster than the wind.

In the boat's frame of reference (assuming steady nonaccelerating state, inviscid flow, etc) the sail can be oriented such that any (sufficiently) diagonal headwind (or tailwind) is redirected more into the sternward direction (with the same speed, by conservation of energy), such that the reaction force on the boat (while mostly perpendicular to the keel) has a positive component in the direction of the bow; (neglecting friction) a sailboat can accelerate forward as long as the wind relative to the boat is not arriving directly from the front.

In the water's frame of reference (assuming the boat is already moving forward) this redirected breeze is always slower than the incoming wind (draw the trig'), losing energy and momentum to the boat (later frictioned to the water), independent of how fast this lets the boat accelerate compared to the windspeed.

The simple idea behind the fan and wheeled trolly contraption is that the belt (which couples their respective axels) performs exactly the role of the sailboat's keel (imagine sailing on a ringworld).

The belt/gear ratio constrains the propellor-tip to move through space on a fixed helical trajectory of constant diagonalness (the ratio of forward to transverse motion, or pitch to circumference), ensuring that (as long as the atmosphere is moving forward relative to the ground) the propellor tips are never moving directly into the wind and thus (identifying the propellor blade with a yacht's sail) a forward thrust component can be obtained regardless of whether the velocity of the cart itself is less, equal or more than the wind velocity.

The limiting factors are the aforementioned ratio, the fixed-angle pitch of the propellor-tip's blade-sail, the windspeed (relative to the ground), drag and friction. For any constant windspeed, the ratio and the propellor sail-pitch together determine a maximum cart velocity (downwind relative to the ground) at which forward thrust can be produced (this can be larger than the wind velocity but not infinite) but it is a tradeoff because the ratio simultaneously increases drag, and (with the ratio also fixed) tuning the propellor sail-pitch for higher cart-velocity decreases its efficiency at lower cart velocities.

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OK, it's either a hoax or an appalling measurement error (I vote hoax).

Geez, DrewDad, You are that unwilling to accept the possibility (however unlikely) that you might be wrong?

Go back and take a physics course that is advance enough to have forces vectors and that is not all that advance as my high school offer such a course in 1966.

I've looked at the blog, and yes, I think the whole thing is a carefully orchestrated hoax. If it's not, then then they are appallingly bad at measuring scientific phenomena. (Which, I grant you, could be the case.)

No - drag on the wheels should match thrust from the propeller + thrust from the sail in a perfect world...