Hi,
I am trying to check the engine thrust angle on my 90 size pattern ( YS-110FZ )
by measuring the distance from the rudder to both prop tips.

Left = 156.6 mm
Right = 154.8 mm
Prop diameter = 14 inch

do you know how to calculate the angle ? my estimation is that the angle is about 3 degrees

my problem is that i still need right rudder compensation ( 3-4 degrees ) is it make sence that the thrust angle will be greater then 3 degree ? let's say 4 ?

Thanks,