Is common air plane flight OU?

[L4ZEP]

@fritznien
Dear friend, you can't write what you want without a Lilienthal-Diagramm of a Cessna. It would be very messy. The thrust of the machine is a function of the motor, in the direction of the centerline of the airplane. The lift-force is a non-linear function of the velocity and the Anstellwinkel of the airfoil.
Please excuse me with my bad english, i'm only a german engineer.

[schuler]

  Dear Gianna ,

Thank you for spending time thinking, writing calculations and putting effort to explain your point of view. I could not expect more. This is much appreciated. Now, I see how interesting is your proposal by bringing gliding to the topic. It makes easier to think with gliding because we can get rid of the power/thrust topic and concentrate on force/energy.

Your example is very useful. Assuming you are gliding at constant speed and direction, the resulting force is ZERO (drag compensates thrust and lift compensates weight). In this case, the thrust comes from the potential energy being converted into kinetic energy. The drag opposes inertia but the loss of altitude compensates the drag. I'm assuming there is nothing new here as you are a pilot. I'm writing this paragraph to help my own thinking.

Assuming that the gliding is gravity powered (instead of engine powered), I'll calculate the energy lost as a variation of the gravitational potential energy (dEnergy = m · g · dh). Where dEnergy means energy variation and dh means height variation. Therefore, the variation of potential energy per second is 1000kg * 9.8 * 3.3 = 32340J/s or 32340W.

1HP = 745W. So, we have 43HP.

Amazing: we are both getting the same result.

At this moment, we both agree that, in your example, the gliding is spending 43HP from the gravitational potential energy.

To be continued...

Thank you for providing fun.

[schuler]

  Hi Fritznien  ,

I think that I'm in the right forum because I intend to debate with intelligent and open minded people. I don't intend to debate with people that has faith that OU is impossible. I prefer rational based debates instead of faith based debates.

looks like a form of leaverage.

Please elaborate your point of view towards leverage. In the case that there is some sort of leverage (force multiplier without OU), where the "hinge, or pivot, called a fulcrum" is located? It seems to me that we have 2 options:

1) Leverage or
2) OU.

To be continued

[schuler]

Hi l4zep,
I'm not sure if I understand you nor I'm sure about the need for the diagram.

I have a perception that the debate doesn't involve fluid dynamics yet as the amount of air pumped down from wings (creating lift) can be calculated using Newton physics.

Please elaborate.

[tagor]

Hi 

In a sustained horizontal flight, drag compensates thrust and lift compensates weight. So, the resulting force is vectorial ZERO. If the resulting force is zero and lift is bigger than thrust, from where comes the extra force?

Have Fun

you need to learn this

http://en.wikipedia.org/wiki/Bernoulli%27s_equation

and this

http://en.wikipedia.org/wiki/Aerodynamic_lift