throttle failsafe calibration

I wrote a blog post explaining throttle failsafe calibration (because I couldn't find an explanation I found clear enough and it took me a while to understand it!)

It's for a Spektrum DX8 and AR8000 but I the basic theory should be the same for most other transmitters and receivers:

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  • Wow - a great explanation.  Thanks

    Now I have failsafe working in theory.  But I want to test it using Mission Planner before trying it out.  I have a copter using the latest firmware 3.1.3 and MP 1.3.0.  Here is the problem:

    I power the copter and Spektrum DX8 up and USB into the computer running mission planner.

    Arm the copter on Mission Planner Flight Data Screen and it says ARMED

    I run the throttle up and am in stabilize

    I turn off the Spektrum radio

    The MP Data Screen indicates that the copter is DISARMED and is in LAND mode

    NOT GOOD if it's really disarmed plus I have the Failsafe set to RTL not LAND

    I turn the radio bak on and switch from stabalize to stabilize and the copter mode changes to STABILIZE but is still disarmed per the DISARM on the MP Flight Data HUD screen

    Anyone else know how to fix this?  Looks to me like a MP software issue.

    Does the Failsafe work in flight anyway?

    Help Please


  • This information is what I was missing when I built my first quad. I thought I had the failsafe set properly but did not because my throttle range was incorrect. When I went to test the failsafe, while in the air, my newly built quad flew away...never to be seen again. If I'd had your info back then I would have saved my quad (and about $600).

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