Wing - Airfoil Type - How Can I Tell?

Question: How can I tell what airfoil type is used on my model?

Answer: This is usually listed in the specifications for the model but if you can't locate the specs, not to worry. There is an easy way to determine the general type:

  1. Check the wing root (or wing tip if the root is not accessible).
  2. Draw a line from the leading edge to the trailing edge (or align one edge of low tack masking tape if you don't want to leave any marks later on).
  3. At the Thickest part of the wing, measure the distance above the line to the top skin of the wing and measure the distance below the line to the bottom skin of the wing.
    1. If the line is coincident with the bottom of the wing, the wing is a Flat Bottom Wing (also often referred to as a "Clark Y" wing)
    2. If the distance above the line is greater than the distance below the line, the airfoil is Semi-Symmetrical
    3. If the distance above the line is the same as the distance below the line, the airfoil is Symmetrical