hi PBL, thanks for your response, but i am still a bit confused, and i guess it comes down to what i've read (or haven't read).
why for a jet engine, point of Min Total Drag is equal to max endurance (i can see this since thrust is also lowest, and assuming fuel varies directly with thrust this would be the minimum required to keep the plane airborne), and on a piston plane, the point of min drag is used for max range since it gives the best L/D ratio?
from what i understand, max endurance on a piston plane comes from min power, but how come this min power doesn't correspond to the min point on the total drag curve? is it because the fact that piston engine doesn't provide the thrust directly?
sorry for the questions, just finding this really confusing, which it shouldn;t!
cheers,