Firmware 1.10.1 Stable Release Motor Disarm Issue in Flight

During my test flight on Saturday, the aircraft disarmed the motors while in manual flight mode. I have been using PX4 software for years, and this is the first time I have encountered such a situation. Telemetry and SD Logs are below. Thanks for support.

Telemetry Log ->

SD Log ->

Thanks for sharing, we’ll have a look.

Hi @mehmetydz87 ,
You apparently triggered the arm switch and this is why the drone disarmed in air:


It could also be that your RC glitched or started to send wrong values.

Best regards

Hi @bresch

I started the flight with automatic takeoff, I did not arm from the remote controller. My remote controller is Spektrum DX9 Black Mode 2 and DMSX receiver.

Yes, there may be a problem due to this “It could also be that your RC glitched or started to send wrong values”.

Also which log analyze program do you use ?

I have experienced this, it turned out to be a slightly sticky arm button on the GPS, so something that can happen over time. Unlike Arducopter, PX4 will disarm if it sees a button pressed even when in the air! Crazy!

What setting do you have for Channel11? The Disarm is at the same time the signal at Ch11 ended.
This is from tlog file.

br HE

Hi

I have no settings for CH11. I reviewed it again after your comment, yes there is a change but CH11 has no assignment. Thanks

Dear Vulcan,

In my opinion, disarming motor after starting the flight should not be connected to a single button. Kill switch is dedicated for this issue.Also a stick combination is necessary.

Here is your ulog uploaded to the PX4 Flight Review.

Looking at the full parameters you have no kill switch but you do have an arming switch configured.

RC_MAP_KILL_SW, 0
RC_MAP_ARM_SW, 5
RC_MAP_FLTMODE, 7
RC_MAP_RETURN_SW, 8
RC_MAP_OFFB_SW, 9

Watching that channel in QGroundControl with the tlog I see it used between flights but not activated near the end. The throttle increases while the servo outputs are falling so it doesn’t seem to be an RC glitch, though the reported RSSI did look a bit low during the flight. I can’t seem to confirm or deny the explanations offered so far.

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Thanks for support @benasena. What do you think about this issue @bresch ?