Arduplane Failsafe RTL not working

Hello, I’m hoping someone can help. I’m setting up arduplane with the latest version. All works well. However, when I test failsafe it only stays in loiter mode. What am I doing wrong? I’ve setup the short-failsafe, and also the long-failsafe. PWM throttle min value as well. Anything else I should be doing? I have 1.5 seconds for short and 5 seconds for long. When I turn off my radio to test it only stays in loiter. When I take it out to the field and flyout, turn off the radio it does the same…only triggers loiter despite specifying RTL in long-failsafe. I would appreciate it if anyone out there can assist.

thank you


Please post a log file or parameter file.

@Allister Thank you for your response and interest in helping me troubleshoot this. Please see attached parameters file. I’m certain it’s something simple that I’m overseeing. Mini-Talon.param (20.4 KB)

The FS_SHORT_ACTN=2 meaning it should go into FBWA but that would only be for a few seconds till the FS_LONG_ACTN takes over and should go into RTL mode.

The THR_FS_VALUE is 925. That looks low to me. Do you know what value your FC is seeing on the throttle channel when you turn off the radio? You mentioned you’ve tested this in flight. Could you post the log for that flight? That should show the exact value we’re looking for. The throttle channel value needs to go below the THR_FS_VALUE for the failsafe to trigger and many RX will send a signal around 975-990 when they go into failsafe.

Thank you once again @Allister. I’ve made some tweaks based on your input. I’m going to do another test flight tomorrow. Will keep you posted.

@Allister good evening. Apologies for the delayed update on this topic. I am pleased to inform you that I have discovered the solution. It appears everything on the firmware side was correct. Seems the issue was on the RX side. I am using TBS crossfire. There is also a failsafe setting in the RC side that either allows you to persist a signal or just “cut-off”. Because AP Plane is looking for an actual cut-off from the rx/tx, it would not allow the firmware to execute to RTL given the RX is consistently sending ut a signal. I just set it to cut-off in the TBS settings and RTL works perfectly now. I wanted to share in case anyone using TBS out there that may be experiencing the same issue can now find the solution. Again, thank you for taking the interest and time on helping me. All the best!

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