Have questions for the aeronauts to answer pertaining to wings. I have seen more than one way to measure the below in publications and plans dating from the late 1920's to present date.


1. How is wing area determined?
a, measured vertically with wing laying flat
b, measured vertically with wing set at proper dihedral angle. (This can make quite a difference on a free flight model with large dihedrals).


2. How is chord length determined?

a, measured horizontally as overall length with wing laying flat
b, measured from farthest point of trailing edge to farthest curve of leading edge.
c, measured along b, but at flying angle for straight and level attitude.
d, measured from farthest point of trailing edge to farthest curve of leading edge when set into proper incidence angle in fuselage.


3. How is dihedral angle placed in degrees when not noted via offset on plans?

a, Along top surface of wing.
b, along bottom surface of wing
c, along centerline based on the taper of ribs from the average of top and bottom surfaces.
d, through center of rounded portion of wing tip, no matter high or low.



4. How is wing span determined.

a, it is the actual overall width of model at furthest point of wing tips.
2, it is the accumulation of all the portions of the total wing as measured flat on plans.


Now rotating angle of incidence, dihedral angles to get different distances may make for just a few thou in measurements on a model, but it does make for a couple square inches when calculating wing areas.


Wm.