This is, what happend today, maybe someone can explain it to me or maybe someone had the same problem.
Normally, when I start flying, I test around a bit without goggles if everything works fine, check flight modes, do some turns aso, just to see if everythings works fine. When I feel confotable I switch to level or altitude hold mode to pull down the goggles, without landing, because I want to avoid, hard parking on the battery. This was always a good way to step in smooth.
But today, after I switched to altitude hold mode it took a few seconds, I was just pulling down my goggles, the quad went straight up about 25 meters. I pushed down the throttlestick without any noticeable result in motor noise or rise rate.
I switched to level mode , thought the problem had to do something with misconfigured altitude hold mode or defective baro. I gave some throttle to recover, but instead of going to a level filght, the quad did a backward flip, about 130 degree and was heading downwards with increasing speed. I wasn´t able to catch it, so I decided to disarm.
The results, don´t look really nice, but compared to the sound it did, when hitting the concrete, its not that bad.
I wouldn´t make a big deal of this and as always, first blame it on me, but this time I think, there might be a bug, because when I thought about it further, I realized, this happend before, at least two times, maybe even more often.
First time about a year ago, with an OG Brain flight controller - first quad, I was a noob and I thought it was a problem with configuration, switches, whatever. Rising very fast, flipping backwards after switching flight modes and than chrash.
Second time, Sparky II - other quad, testing around with my taranis and flight modes, thought again, that I made a mistake. setting the wrong flight mode, getting nervous and crashed. Same pattern - rising, flipping backwards, crash
And now, other FC, Brain RE, other Quad, but again, the same pattern, just with a more powerful quad, so it happend faster.
Thinking more about I realized, there had been some of this situations, when I was indoor testing without propellers and the motors were raging around, when I switched flight modes, until I disarmed. I never found a reason and I could not reproduce it so I always thought it was something, that the FC where somehow reacting in a weird way, because of no props.
What do you think about this? Any ideas and thoughts?