Yes Jim your statement is correct
I was trying to clear up the 4.4° difference of his longerons and keeping the level with the proper end not to add or subtract from the angle.
When you zero the level on the longeron and rotate the level 180° the true angle of the longeron is 1/2 the angle shown.
If you properly calibrate the level and rotate the level the angle should read the same.
Then you can see that the longerons are not 4.4° different
Using the pilot side is ok however the side closest to the true line of thrust will get you to the most accurate angle.
The target of 71.4° is not 100% correct if the longerons are not in perfectly in line with the line of thrust.
The 71.4 is close enough as a starting point and may need to be changed for the best rate of clime or for the cruse speed.
Originally Posted by Piper J3
Actually, no. You want to zero the level on the longeron. Use the copilot side because that is the side of the prop you will measure prop blade. The pitch angle is the difference of blade angle as compared to reference angle of longeron. Airplane need not be level...