The KAI recommends that the final riveting on the flap and aileron leading edges is completed with the parts connected to the wings. This is important step is required to match the twist that has been incorporated into the wings. Failure to perform this step will result in degraded performance and a "heavy wing" that will cause the airplane to roll on the longitudinal axis. This step also requires the wing tips to be installed as the trailing edge alignment is a critical part of the alignment process.
In my case, I had not finished riveting some of the skin in place so I needed to complete this step.
This work needed to be completed on both the flaps and ailerons, leaving the last row open on the leading edge until the next step.
Flaps are clamped in place to align the training edge with the wing step edge.
Ailerons are also aligned to the edge of the wing tip and clamped in place.
With a small amount of twisting the ailerons and flaps, the alignment of the leading edge was ready for riveting.
Next I removed the clamp on the flap and pulled the first few rivets in the center of the leading edge. Then you re-position the flap and secure in-place with the clamp and check alignment with the aileron.
At times you will need to continue to make small adjustments flexing the part to keep it aligned with the aileron.
Also to keep the shape that you have introduced, you may need to match drill some of the holes on the leading edge to avoid removing the twist when riveting.
This process is repeated multiple times as you place rivets, working your way from the middle outwards on both sides towards the edges of the part.
This entire process is then repeated for the aileron, checking and re-checking alignment with the flap training edge until fully riveted.
You end up with the same initial alignment set at the beginning of the process.
This should remove the need for trim tabs on either wing to compensate for any roll in the longitudinal axis.
The process is then replicated on the other wing completing the wing assembly.
