About three or four weeks ago, having assembled the Octo, I set it down outside in the garden for its first test flight. In no way did it behave as I had been expecting. It wanted to go forwards and hard left. Whilst on the ground a couple of the props were just sort of marking time but not spinning like the others. So, I waited for the next day and went down to the flying field where I could be a little more 'adventurous' with the throttle. It pitched around wildly and eventually flipped upside down - twice.
This was not the easy drone experience I had been expecting at all. For the umteenth time I verified the flat horizontal setting, motor directions, individual motors and response to transmitter commands. All the motors sped up or slowed down correctly in response to Tx stick movement. So, WTF?
Then I tried that 'holding it aloft while my lady fed in throttle' thing and I could feel it wanting to tip forwards. I let it tip and then eventually it corrected backwards but FAR TOO much and then far too much forwards.... There was clearly some sort of gyro problem. I took the FC board off and lo and behold there was a great gob of solder splattered all over a small component (a capacitor it turned out) next to one of the gyros on the small upright board. The capacitor came off anyway when I tried to remove the solder so I cleaned it up and replaced it and then ... everything was OK.
Your 'first official test flight' sounds remarkably similar to my experience so you might want to check the boards for solder blobs shorting out stuff? All this was related in another thread at the time but for now I am posting the photo of the solder blob again for you. It is top left on the right hand gyro board.
Boris mentioned something about checking stuff in KopterTool. I hadn't even considered that. So I did and I am much wiser for it (thank you Boris!).
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