Servers by jDrones

My easystar-II yaws to left while giving thrust in FBWA mode


(Am) #1

Hi all,
My easystar-II is yawing to left while throttling up due to the motor torque in FBWA mode.But it tracks straight at 0 throttle gliding.So its not trim i guess.I found that the amount of yaw is kind of proportional to the amount of throttle.Is there anyway arduplane can give counter rudder depending on the throttle?

Should i try to increase the value of KFF_RDDRMIX?

Sorry i am totally new to arduplane and still learning.Please guide me.Thanks.


(Hunt0r) #2

I am surprised that you think it’s due to motor torque. Your testing whether or not it glides straight was a very good one, but I have a few other hypotheses for the cause:

  1. I would suspect the motor is mounted at an angle (e.g. pointing “left” instead of straight forward). Could this be it?

  2. Another possibility, if your motor is mounted straight, is that perhaps your vertical stabilizer (aka vertical tail-fin) is not mounted straight? The prop-wash could put a yawing force on a not-straight tail. Could it be this, perhaps?

And I don’t believe any setting exists which adjusts the rudder in proportion to the throttle… someone please correct me if I’m wrong!


(Joe Breznai) #3

Down and right thrust can do wonders to the power-on trim pf an aircraft. 2-3 degrees right thrust can make a huge difference. You can use washers as shim on the motor mount.


(Am) #4

I think you nailed it!!

After reading your post, i checked my motor and vertical stabilizer and found that my vertical stabilizer is not perpendicular.If i look at the plane from behind,its tilting slightly towards to the left.Now i need to find a way to straighten it up.Maybe hot air gun.I haven’t glued the two halves but just taped it using fiber tape.Will try to fix my vertical stabilizer and test it again.Thanks hunt0r!!