Is there an in flight test for yaw trim? I know “center the ball” but how do I know the “ball” on my PFD is calibrated correctly?
Put an electronic level across the fuselage and let some air out of one of the main tires to level the airplane side to side. The ball should be in the middle. If it isn't shim your ADAHRS unit until it is.
That takes care of the roll axis alignment but what about the yaw axis?
The T33 had a string mounted on the nose of the aircraft that the front pilot could see while flying.
It was used to correct yaw during flight by adjusting rudder trim.
Carr
So If i'm reading this correctly, are you thinking that the airplane is flying in a crab in unaccelerated wings level flight? Not with respect to the ground, but genuinely flying in a crab through the air mass with the ball centered?
If that's the case, Then about the only thing I can think of is to tuft someplace out of the prop wash and maybe take a peek with a go-pro.
In a practical sense, if the ball is erroneously centered, it also seems like it would always break toward the "upwind" wing in a stall.
Did I win?
Yes...not by much, I think it’s half a ball out. I’m looking for a method to determine if it really is half a ball out.