[KrisW]

Funny thing is. . if I trim my plane according to Benny's way of doing it. . it becomes a nose heavy PIG long before I ever get to try a 45 degree line.

If you are adding up elevator trim to a plane, then it is tremendously nose heavy, IMO

Most planes require positive incidence, or down elevator trim, on the tail, to fly level, because something has to make the tail lift, and the only way to do it is by giving some lift to the stabilizer Even a Sr. Telemaster uses this. Rolling inverted, with "down trim", will make the tail droop, but the wings incidence will increase, keeping the aircraft flying straight and level. You can actually see this change in AOA by watching closely and comparing the planes angle when inverted or upright.

This is borne out with . . . what happens when you roll inverted??? A truly "neutral" plane will just keep flying level, no matter if it is upright or inverted, once it is trimmed for level flight. What happens on vertical downlines is an entirely different story, however, because there is no gravity pulling the nose or tail down, and then you get purely aerodynamic forces acting on the airframe, and it will pitch or tuck in accordance with how you have the plane trimmed (assuming 0-0-0 incidence). It will also (even with 0-0-0 and no trim) tuck or pull due to drag on the airframe, especially so with a low-wing design, since the majority of the drag is below the thrust line.

My planes usually require about 2% down mix with the throttle at Idle in order to do a perfectly straight vertical downline. Considering that my time at idle, when flying, is very scant, setting a mix for this works out pretty well.

This is why the "45 degree test" is probably the most accurate test of the planes overall CG and trim. It will show tail heaviness that would otherwise be mistaken for a "Neutral" plane on a horizontal line, and will ignore most trim or incidences that would make an aircraft pull or tuck on a vertical downline.

Peter Goldsmiths techniques may be "old fashioned". . but they have been shown to be extremely helpful and accurate when setting up a plane for best overall flying performance. The object is to get the plane to fly straight, with a minimum of control inputs. .no matter what kind of plane it is. And with an aerobatic aircraft, following Peter's recommendations will get you the truest flying plane in any attitude or orientation, and at 90% of throttle settings.