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Roll trim, non-trailing ailerons

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trex

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Joined
Oct 13, 2012
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Hello,

I've been working on the rigging of my Firebolt 540 and I have a question, but first some background information: the aircraft always had a "heavy" right wing and yaw to the left (roll and yaw in opposite directions). I've spent considerable time getting the wings straight and tension in all wires where I like it (BTW, my starting point was the 600-750 lbs tension mentioned in Skybolt News Series #4 Vol. #1). With 750 lbs in the landing wires, the flying wires vibrated in flight (at 195 mph) so I tightened them further. The tension in the landing wires is now over 750 lbs while the tension in the flying wires is still quite a bit below 600 lbs. I use a calibrated precision tensiometer. Recall that the Firebolt has three flying wires and two landing wires.

After rigging the wings to +/-0.1 deg left to right at essentially every butt line, I adjusted the four ailerons to perfectly trail the wings.

Now, during flight tests I kept the ball centered and the ailerons in perfect trail and then there is no roll, which is very good. However, when I let go of the stick the ailerons on the right side deflect up and those on the left deflect down, and the aircraft rolls to the right. My guess is that there is some imperfections in the ailerons that make them trail non-symmetrically. Has anybody experienced this? Or better, does anybody have a good remedy? Spades could cure it but I don't have any at this point.

Thank you!

Trex
 

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