Originally Posted by
HighPlains
As I said in my first post on this thread, I have never cared for the design of the PT-40, even though I knew the designer. It is too stable to be a good trainer. The best thing would be to take out the radio and fly it as a free flight. Eventually the wildly excessive dihedral was reduced, but with the decalage and balance when built strictly to plans makes it a poor trainer when compared to an Sig LT-40. I think that suggesting a few changes to improve the handling is not out of line and well within the abilities of anyone with a loose association of the English language.
I think that most trainers have too much positive incidence for my tastes. A cambered airfoil such as those found on almost all trainers already will climb with power, without exacerbating this with more positive incidence. I personally like them set to zero relative to the stab.
I cannot remember if I have flown a PT 40, most likely I have, but I do not remember a problem. It would not surprise me if it did though. I think the worst one I have flown though is the Nexstar. They over thought that design, and stock they fly like cap.
That is a good point about altitude. It makes a huge difference. So while a .25 might be good at sea level, it most likely would not at mile high, such as where I fly. Not sure about altitude and wind, but we sure get our share of it. We have a lot of calm days though as well.
One design I always heard great things about were the GP trainer series. The 20, 40, and 60. This was a Joe Bridi design and had a fully symmetrical wing. In spite of that out of the ordinary design difference, they are known to be one of the best trainers ever designed. I always loved the Telemaster as well.