Now that you have set the for/aft CG and engine thrust line, it is time to check the balance between the wingtips. Before
you start this test, you must make sure you have sealed the aileron hinge line. The problem with unsealed hinges is that no
two gaps are exactly alike. When maneuvering, the air will react differently as it passes through the left and right aileron
gap, and that will give you asymmetric lift on the wing. There are also instances where control flutter has been stopped simply
by sealing the hinge gaps. All it takes is a strip of tape or monokote.
Start by flying some up-lines to trim in your rudder. Fly them at full throttle and in both directions, so you will be
sure to negate the effects of any wind. Once you are certain the rudder is trimmed, fly some level lines at half throttle
and make certain your aileron trim is right on.
Now the test…roll the plane inverted and push just enough to hold level flight. Do NOT hold any aileron correction.
What does the plane do? If it rolls to the left when inverted, then your right wingtip is heavier than your left - so add
a little weight to the left wingtip. Likewise, if it rolls right, add weight to the right wingtip. After adding weight, you
will have to re-trim the rudder before rechecking.
Once the lateral CG is set, the plane should not drop a wing when starting a pulling or pushing maneuver. Note I said when
“starting”. If you do a full loop without adding a bit of rudder, every plane will eventually yaw…and then
drop a wing. We will discuss this later, though.