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Someone explain Lift / Drag stats for wings

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I'm really confused over the information proved for airfoils - specifically the lift / drag stats and their measurement being given in degrees. For example:

- A small aileron Lift/Drag = 9.0 degrees

- A small wing Lift/Drag = 7.0 degrees

- A small stabiliser Lift/Drag = 5.0 degrees

Can anyone please explain to me what do those degrees represent, mean, and how those measurements are calculated as that makes about as much sense to me as measuring the length from point A to point B in cubic litres :( 

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I don't know why it says degrees, I think people have been wondering that for a while. Not sure how it is calculated but it should be a ratio in my understanding, so ailerons have the best lift to drag ratio, and stabilizers have the worst and wings are in between. But wings have a higher stall angle, so there are other things to consider when choosing what to use.

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42 minutes ago, Haunty said:

I don't know why it says degrees, I thing people have been wondering that for a while. Not sure how it is calculated but it should be a ratio in my understanding, so ailerons have the best lift to drag ratio, and stabilizers have the worst and wings are in between. But wings have a higher stall angle, so there are other things to consider when choosing what to use.

Im not an expert, but i will try to help. 

Fist think you can try is to enable the wing widget. 

If you link a wing to the seat and rename its unit( in the lua interface) to wing1 you can now do wing1.show()

This will show a widget that tells you several realtime values on that wing. 

 

There are 3 types of wings:

Ailerons - best drag ratio, worse stall angle

Wings - average drag ratio, average stall angle

Stabilizers - worse drag ratio, best stall angle. 

 

All behave exacly the same. All can stabilize and all can create lift. 

 

All wings will can create lift and its related to the velocity the wing is traveling and its parallelism to the ground. 

What this means is that a 45° wing will create cos(45°) lift when the craft has a roll of 0°. And 100% lift if the craft is tilted 45°

 

The stabilizing happens when the wing traveling is below the stall angle. The stall angle is only affected by the angle perpendicular to the wing and the stabilizing only happens perpendicular to the wing. 

While stabilizing, the wing will convert velocity(kinetic energy) into perpendicular force, efectivly changing the craft velocity vector to where the wing is pointing. 

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Excuse me for the probably dumb questions, if you say "a 45° wing will create cos(45°) lift when the craft has a roll (not pitch) of 0°" it does imply that a 90° wing won't create lift at all (cos90°= 0), but then why do people use stabilizers as wings? :V

Also is the stall value you find on airfoils description an angle? I mean, wings have a stall value of 55, is 55 the angle at which wings stop working?

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The simple explanation is that if you press X to see the velocity vector arrow, a wing will stall (no longer generate lift) if you rotate your construct so that the wing lift angle perpendicular to the velocity vector is greater then the wing stall angle. In other words higher stall angles means you can make quicker turns without stalling.

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Ok, but how does that "drag" unit factor in? Bigger number = better? I would have thought that it would be the opposite, but then stabilisers would simply be superior to wings in all respects.

 

Does it simply mean the maximum angle at which the wing performs at its best?
ex: Stabilisers would have some lift up to a 70 degree angle, but only give out max lift within a 5 degree angle vs. an aileron which would only give lift at no more than a 30 degree angle and give out its maximum lift at up to a 9 degree angle.

 

Just noticed that ailerons have an "angle control" stat that the other two do not have at all. What does that mean?

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Drag is bad and you want that number to be as small as possible. My guess from a real life perspective is that the given angle is the angle of attack where you get the highest ratio of lift coefficient to drag coefficient. Typically thats displayed on a graph and is unitless, but thatd still be my best assumption for this. 

 

I think eruend has closest idea of what it is saying. Just with the opposite idea on drag. The game obviously does not perfectly calculate what happens with lift and drag forces but it does okay.

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