@drkohler,
I see what you are getting after now.
I would like to point a few things out, lets see if we can work this out: First I am going to talk about the wheels a bit, as I think this is a point of misscommunication. Then I am going to move into your example and explain a bit more about why I brought up this topic again.
If the wheels are free-spinning, which is standard for all planes, the plane will be able to maintain a stable position with little effort.
For this situation lets assume the plane has already become stationary on the treadmill. Now the only external force being exerted on the plane in this situation is the treadmill\\\'s friction on the wheels. Whenever you have a surface tangent to a free-spinning wheel and there is friction as they move across one another the result will be that the vast majority of energy from friction is expended in spinning the wheel.
The rest of the energy is transfered through the wheel axle and into the frame of the aircraft which will result in \\"acceleration\\" in the same direction that the treadmill is traveling. But this acceleration is minor compared to the amount of energy being lost in spinning the wheels.
The result is that it actually doesn\\\'t take but a small amount of extra energy to maintain a given speed on the treadmill versus off. The plane won\\\'t need to expend a lot of energy to attain a stationary position since all it needs to do is overcome the small amount of force that actually makes it to the frame and any extra thrust it produces will counteract the starting momentum and it will \\"move forward\\" and will continue to do so until it not only passes a \\"stationary\\" position/speed but until it is traveling forward fast enough as to produce wind resistance that offsets its \\"extra thrust\\".
The reason I point this out has to do with your idea of a plane designed to produce airflow over the wings. The plane clearly cannot take off without first attaining a "stationary position", I think we are on the same page with that part but I am stating for clarity. So this is where what I was just talking about comes into play. If I am reading you correctly you are saying it will be able to produce enough airflow on its wings while stationary to take off. But I think that the amount of thrust it will be producing to create that airflow will have it moving forward long before it takes off for the reasons I stated above.
I think an aircraft designed to take off purely from the airflow it produces and nothing more is possible, but I don\'t think it can take off from a stationary position soley with the aid of a large treadmill.
PS - I am oversimplifying everything to make sure we are on the same page every step of the way, it also makes it easier if we have different understandings of a concept so that we can sort that out before dealing with the larger issue with a compatible set of terminology.
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