More fiddling around with P3D v5.2HF1.
I am not finding many aircraft that ran ok in v4.5, doing so when loaded into v5.2HF1.
One that is though is the Jahn/Visser C-47. Absolute gem of an aircraft.
This one is headed North East in Washington State.
(I lost the top of the screenshot to a jagged line across the shot. Above the line it showed distant mountains)
T45 (P3D v5.2HF1)