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How do I find the best airfoil?
The airfoil you choose is going to be a determined by the desired operating parameters of your design, each requirement you add will have input to your airfoil decision. For Example: Thin symmetrical airfoils are great for aerobatics but not for lift – see the Extra 300 vs a Zenith CH801.
How do you size an airfoil?
Multiply your x and y coordinates by the scaling factor you want. Say your chord length is 100mm. To make it 150mm, multiply all your values by 1.5. If you have a picture of an airfoil, just scale the image by 150%.
How is the camber of a NACA airfoil determined?
This NACA airfoil series is controlled by 4 digits e.g. NACA 2412, which designate the camber, position of the maximum camber and thickness. If an airfoil number is M is the maximum camber divided by 100. In the example M=2 so the camber is 0.02 or 2% of the chord
Can a NACA airfoil be the best choice?
So you know your wing planform and look for the right airfoil. You need to be more specific with your requirements, and yes, NACA airfoils will most likely not be the best choice. But since there is plenty of literature on them, they are a good start. Please answer those questions first:
How to calculate the final airfoil envelope in NACA?
The equation for the camber line is split into sections either side of the point of maximum camber position (P). In order to calculate the position of the final airfoil envelope later the gradient of the camber line is also required. The equations are: The constants a0 to a4 are for a 20% thick airfoil.
How do I choose the correct airfoil for my aircraft?
Your choice of the NACA 64₃618 is a good start. I would advise, however, to taper the wing to something like a NACA 63₃412 at the tip. Thinner airfoils have lower minimum drag and higher maximum lift coefficients which helps to avoid the tip stalling first.