Is common air plane flight OU?

[schuler]

  Hi Tagor,
Thank you for sharing the links. When you say that I should learn "this", what "this" refers to? Should I understand that "this" means "the second law of thermodynamics" and therefore OU is impossible?

Mathematical and computing models are modelled as tools to understand reality. They are models and not reality.

It is known fact that the Cessna's 210hp engine can't lift (can't sustain an ascending vertical flight) 2,300 libs, therefore, thrust is smaller than lift. Fritznien proposed that there is some sort of leverage somewhere. I like that way of thinking. Thank you for sharing.

If we estimate that the average vertical component of the downwash of a Cessna 172 traveling at 110 knots to be about 9 knots, then to generate the needed 2,300 lbs of lift the wing pumps a whopping 2.5 ton/sec of air!

Energy = 0.5 * mass * (speed ^ 2).

9 knots = 4.6 m/s

So, the energy to pump air is (per second):
0.5 * 2500 * (4.6 ^ 2) = 26450 J.

But this is the amount of Joules per second, so we have 26450W.

Therefore, I conclude that wings from a Cessna 172 traveling at 110 knots produce a minimum of 26450W.

So, if there is a way to create thrust big enough to compensate drag with less then 26450W (35HP), I think that there is over unity.

In the case that you disagree, please share your calculation.

Have fun.

[schuler]

  Well....
There is another way of thinking...

Drag depends on the shape of the wing (among other parameters), so we have 2 parameters towards OU(among other parameters):

1) How efficiently the engine transforms its energy into thrust.
2) How efficiently the wing produces lift with a minimum drag.

If you are able to compensate drag with less energy than produced by the wing, you have OU.

To be continued

[tagor]

Well....

2) How efficiently the wing produces lift with a minimum drag.

the efficiency comes from the cuanda effect

look at J L naudin lab , he has done some experiment on this effect