Recent content by jduffy77

You are correct.

Yes, with the most important point, (for kmarinas) being that the wires are necessary.

Agreed and one consistent feature of all sails is they can not drive something faster than the media which is pushing them without leverage.

Congratulations, you have designed a PM machine.

Are these props powered only by the stream?

No but the steel rod is required. We were talking about the ability of a balloon which you said could "act like a sail" to travel ddwfttw.

The craft needs a fulcrum.

It is not because it is not efficient enough. it is because it is impossible. There could be no mechanism to extract energy. But it can't. Maybe now we are getting somewhere. The sailboat needs the water or more importantly the keel. It cannot.

You are wrong, the leverage is central to the carts functioning. A cart could not ddwfttw without the ground any more than a balloon could. Your diagrams above introduced two more scenarios which have absolutely nothing to do with the cart. The cart can travel ddwfttw indefinitely. It is not...

No, I only said that dynamic soaring has nothing to do with the ddwfttw cart. It is true that both extract energy from the difference in velocity between two masses but that is as far as it goes. You state that the ddwfttw cart does not need the ground. That is nonsense. There is no shear...

I know what you said, its just that you are completely wrong. Your confusion seems to be fairly well entrenched at this point and I do not really know how to help you. At this point I will answer questions if you have any or hopefully others more expert than I am might chime in and help you...

Kmarinas Have you checked out coolaun's excellent videos? http://www.youtube.com/user/coolaun/videos He shows various d"w"ftt"w" examples.

No, in fact the only thing that does make sense to say about the props power source is that it is the wheels. The ground is in fact the source of energy if you choose to analyze the cart in a frame other than that of the ground. This is completely wrong. The relative motion of the wind with...

This article has absolutely nothing to do with ddwfttw whatsoever. Your apparent desire to over complicate the simple lever which is the ddwfttw cart is fascinating to me. I believe your confusion stems from the fact that you still wish to see the cart as being pushed along by the wind. You need...

Air is certainly being deflected by the prop. It is being shoved out the back which gives an equal and opposite reaction. That's pretty much the definition of thrust. This does not help your first post today make any sense however: