Originally Posted by small_rcer
When a Clark-Y airfoil has the base or bottom horizontal, it has a positive angle of attack.
The reason I say this, is because the angle of attack is "usually" measured from the centre of the radius of the leading edge to the center of the trailing edge.
With a Clark-Y having the bottom as a datum, you could have several degrees of angle of attack.
A simple rule is 1/16th of an inch at 4 inches is 1 degree. So if the chord is 12 inches, 3/16ths of an inch is one degree.
What is the height of the centre of the radius of the leading edge, above a straight edge held along the underside of the wing?
See this link for a sample
In that case I guess the wing position needs to change. Unsure as to the radius of the centre of the leading edge robably around 5mm Ish.
So does this mean I need to give the elev some down trim to compensate? Or would it be best to give ailerons some trim instead?
Cheers for the link, it helps a lot.. Even though it's not what I wanted to see!