GeraldRosebery

My Feedback: (14)

I am finalizing the design of my OPUS 7-90 a 90" aerobat that will look sort of like an Extra. It will carry a DA50. I have built most of my designs so far zero-zero-zero and they have all flown extremely well. I have designed in 2 degrees of right thrust into this model. How do people feel about that? Ask for more info if you need it to advise. Thanks.

tommy s

My Feedback: (55)

That's an interesting question. I fly mostly pattern planes and some of the best
flying ones I have owned were set up 0-0-0 including a few I designed myself.
My first experiment was on a Bridi Kaos back in 1970. I flew it almost a year then
a non flying accident broke the tail off and I decided to use the wing and build a new
fuselage. The Kaos has a large amount of right and down thrust built in but I built
the new one without any right thrust and very little down and it flew better in my
opinion. The only other change I made was closing in the open nose around the
engine. I understand downthrust because a symmetrical wing has to be at a positive
angle to fly. Even if the wing is set at zero, downthrust makes it in reality a positive
angle, but on an aerobatic airplane which everyone wants to be neutral reacting
it seems right thrust becomes left thrust when the plane is inverted. I know there are
some really good airplanes set up both ways but I would also like to hear a good
explanation that makes sense to me about right thrust. I also realize flat bottom and
semi-symmetrical airfoils are a whole different story.

tommy s

Kenny R

Something i have read and then tried on electric planes and seems to work very well is: Set the motor with no right thrust and mix the throttle as master and the rudder as slave with a little testing you can get the right mix to offset any unwanted torque tendencies. I cant find the link to this right now but it was in the Chip Hyde forum I believe.

Tall Paul

Actually you might make provisions for thrust offsets, but fly the plane using any of the numerous flight-trim charts to see what it might need.
All the other stuff on the plane will affect how the entire system flies.