"LOOK MA! NO SKIN!"

THE PROBLEM
I have had some issues with my a stock C186 after testing an optical flow module from an Eachine E110 in it. For some reason the heli started shooting off to the left at launch and crashing. Very odd. So I took it apart for an exam.

What I found was that the rear servo and left side servo seemed to have traded channels. Very odd, as I don't recall unplugging any servos when I installed the module. Did they reassign when I pluggedin the module? I swapped the plug positions on the control board, put it back together and tried a test flight. The bird would take off and start a moderate drift to the left, requiring significant stick deflection to keep it hovering in place. It took most of the righttrim range to get it to stabilize and stop drifting.

SO I have taken it apart again for a test flight without the body on. Since the tail boom is a part of the body shell I had to fabricate a boom from some 3mm carbon fiber round rod I already had. Fortunately the frame has a hole in back for what I believe is a 4mm square tail boom, possible for testing the heli without a body shell on it during it's design phase at the manufacturer.

I put some shrink tubing on both ends of the rod so that it would seat firmly in the frame and in the tail piece holding the tail rotor motor. I cut up a plastic lid from a Pringles potato chip tube to form a simple tail fin to protect the tail rotor from ground strikes. Some black electrical tape holds the temporary fin in place.

The TEST FLIGHT
Upon takeoff I noticed the heli was no longer trying to slide to the left and even had a tiny bit of rightdrift now. It was fine. Not sure what's going on, but I guess I need to check inside the body for interference next time I put it all back together.

Happy flying!