Radio Failsafe - Disarming - Crash

Hi all,
Had a recent crash with a copter and am trying to figure out what happened. Haven’t yet been able to check the TX failsafe settings (this copter is owned by someone else and I don’t have access to the TX), which I know can be a common cause of this, but I’m trying to determine what else might be going on. Did the copter think it had landed after the earlier brief failsafe, hence the disarm on failsafe? Wouldn’t a “land detected” show up in the log in this case? I’m kind of at a loss - VIBE levels look okay - not sure what else to check. Any help would be most appreciated - thanks!

Check out this thread. Your Flight Mode did change to Stabilize.
Radio Failsafe-Disarming

I did look at that thread - but the CH5 value here didn’t go below the FS_THR_VALUE like Randy was talking about in that thread in my case. Even if it did, why would the copter disarm in the air - did it think it had landed? Or FS_Crash_Check stopped the motors? I just thought that would’ve showed up in the log.

I don’t think I quite understand Randy’s comment here from the other thread.

Check that somebody hasn’t set up the old-school failsafes with fixed channel values. The throttle drops to min and the quad changes to stabilized mode, about 1 second before the failsafe is recorded.

Check this out: Radio Failsafe — Copter documentation

If the copter is armed in Stabilize or Acro modes, and the throttle input is at minimum, the copter will immediately disarm.

Looks to me like the quad went to stabilized mode, and throttle went to min when the radio first had it’s error. When the failsafe was recognized by the controller the logic I quoted above was applied and the quad disarmed. The rest is gravity.

Ahhh- I didn’t connect the dots there. That sentence from the wiki clears things up. Thank you both, @Allister @dkemxr

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