Crash on Take off mode. Please help for analysis

I need your help for an analys of my crash during takeoff mode.
Everything was fine for previous flight but in this attempt I didn’t found what happen.
It was a little windy.
During take off aircraft didn’t climb and hit the ground after 20 meters.
Please could you help me. I joined the log


The RCOut channels (3&4) are showing outputs to the servos, but the plane shows no sign of responding to them. This suggests some kind of mechanical issue. Some ideas to looks for:

  • Did the battery move and the C of G was messed up?
  • Was there an issue with the servos? Since there seems to be little response from either elevon I would have a look at the power going to the servos to make sure both had power or that the supply for the servos hadn’t failed.
  • Was there something preventing the servos from moving?
  • You mentioned it was windy, were you throwing the plane into the wind? If you went downwind or even crosswind (if it’s bad enough) that could have caused problems that the plane just didn’t have the authority to recover from.
  • We should also consider the launch. I noticed that at the same time the plane started to accelerate the plane was nose down and stayed that way for over a second. Is it possible it was just a bad throw?

A side note: I noticed you had stall_prevention disabled. That’s a good idea to have that on. It doesn’t change anything for manual or acro mode but is a good idea if you’re in any of the stabilized modes (FBW…)

THANKS ! You re so specialised on your analysis.
Yes I ve launched flat or a little nose down. Due to the wind, this combination should cause the crash.
You ve said stall_prevention is disable, I didn t noticed that. I will active this.

Thanks again for you quick reply

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