A number of years ago I lost a 1/4 scale biplane to a servo that seemed to reverse itself with a Futaba 7UAF. Everything was set and checked out, the plane had plenty of flights on it, correct model was selected, I was ready. Unfortunately, I had numerous interruptions at the field while prepping for the day's flying and omitted a step in my preflight. I didn't check that each throw was correct.

I took off with ailerons reversed. You know the results. Quick roll into the asphalt runway meant the end of the aircraft. I was in shock. After checking everything over I found that the ailerons were reversed. But it had been correct yesterday! Then I remembered that I had gone into programming mode the night before to tweak something. While doing that, I had gotten lost in the menu system. I remembered struggling to find what I wanted. Obviously, I accidently reversed a servo while in programming mode and it caused the loss of the plane.

I talked about it here on RCU and most folks said what caused the crash was the incomplete preflight. While that is a contributing cause, it's not the root cause. The root cause was that I accidently reversed the servo while in programming mode. How to learn from this?

Nobody is perfect. Saying do a perfect preflight every time isn't how you learn from something like this. There will always be the one time you slip up in your usual preflight. The secret is to try to ensure those rare slipups don't sink ships. My answer was that every time I switch a transmitter into programming mode, I suspect that I may have done something wrong. As soon as I take it out of programming mode, I do a quick check of all surface throws.

It might not be what caused your problem, but it's a good practice. Like Flyinwalenda said, you can do it accidently. Think hard about if you went into programming mode since the previous flight. Luckily, you caught it before it cost you an airplane.

I am good at doing a full preflight every day. But one lapse in concentration cost me dearly. Now I double check things when I exit programming.

Dave