Originally Posted by atjurhs
tuan, I just don't see how that can possibly be the case.
Given that a ship is designed to have it's lowest CD is when no surfaces are deflected, not using differential and increasing the amount of rudder deflection can only increase the CD of the ship. And if you're not ultra smooth on your rudder inputs, all the more so. Whereas less rudder and less TE deflection (via differential) must have less CD, hence more efficiency. Perhaps no differential and more rudder input works for your flying style, but I don't see how it can possibly be more aerodynamically efficient.
When I first started out, I used to use the standard 2:1 or even 3:1 diff as all my local experts told me. I also see lots of people holding trans in just one hand and operating right stick only as they had A/R mixed in. I thought, man these guys are good.
Then I found markdrela and read everyone of his posts. I can't find the exact post now, but I remember he wrote something like using diff is using drag to counter the yaw and using rudder is using lift so using rudder, drag is smaller than using diff. Something like that.
I will try to look for the post later.
Anyhow, I still use A/R mix but mixed at rate that makes rudder move lots in beggining of ail movement, but it's on a switch and it gets turned on when I am at limits of my vision without height and for when I let others try my plane. Also, in normal flying I will start the turn will rudder just before adding ail as needed to keep bank angle. So far the X needs almost zero ail once in a thermal bank or even opposite, I just thought about this now, when in opposite your diff is actually working against you.