Level flight requires slight right hand turn input

[B2C2]

I will definitely check the Robertson manual for that aileron setting. 1/4 inch of upward deflection on the right aileron would probably fix most of whats going on. I have the manual but its currently at the shop with the plane and log books. In regard to the flap suggestion I have looked pretty carefully at the flap positions and they seem to be even on both sides.

[DrDave]

Wouldn't the simple thing be to have the rigging checked, in a methodical order, by someone that is experienced in airframe rigging? There are a number of people that have taken the CPA rigging course that could help out. It is so nice to fly a plane that is rigged correctly.

Dave

[B2C2]

I had the rigging redone about two years ago, but it did not effect the flight characteristics. At that time the mechanic used the Robertson manual, and he's pretty careful so I need to check it to see if in fact it recommends the aileron deflection. I will be back in the states next week and will look into it.

[B2C2]

I was able to look at the Robertson rigging procedure today when I stopped by the shop. It does indeed recommend that 1/4 inch of right upward aileron deflection be applied after the full procedure is done to allow for the airplane to fly with trim tabs zeroed. As far as I can tell this was never done either before or after I had the plane re rigged two years ago. I don't know why this is required aerodynamically, but it is part of the procedure. Based on what I have seen this should resolve at least half of the required yoke rotation. The plane is going back together during the annual and we will put this in and see how it flies. I had to do the eddy current spar inspection for 5500 hours so its taking a bit longer to get it back in the air. Its raining cats and dogs here anyway so better to be in a cozy hanger.

[B2C2]

So as a final update I finally got to fly the plane after adding this 1/4 inch of upward right aileron adjustment on a calm day and it now flies a straight heading with no control pressure input and neutral trim tab settings. So thanks for the help and of course RTFM. The yoke is still slightly rotated to the right, in level flight, but no control pressure is required to maintain a heading, so at this point it is purely a slight yoke position adjustment which we can take on at some point in the future.

[DrDave]

Does the plane go faster than before? Are you making book speed?

Dave

[B2C2]

The plane has always been pretty much on book speed. I was trying to decide if it was slightly faster yesterday, possibly 3-5 mph. I will be taking it down to Mexico next week so lots of opportunity to observe cruise flight behavior. I will post if I see a distinct change.