RX Fail-Safe enlightenment!

Ardu Version: V3.2.1 Build: (36b405fb)
Ardu Type: APM:Copter
Hardware: 2.5
Frame Type: H

Main Battery = Activated at 10.3 volts or 650 mAH, with RTL
Ground Control = Not Activated
Receiver = Activated at 950 PWM with always RTL
GEO Fence = Not Activated

This topic might be of interest to some of you that have receiver Fail-Safe parameter activated and to consider the following incident that occurred to me a few days ago. As required, I had FS trigger to a min of 10 PWM below the reading I was seeing while my TX throttle was at its lowest position ( 965), thus my trigger was set to 950. That evening on completion of RTL and the other during a normal stabilize landing, the motors would not completely power down, had erratic RPM and nearly flipped itself over, eventually system responded to my constant left yaw command and De-Armed itself.

Data indicated system had entered FS mode and attempted RTL because readings attained were 942 on one landing and 949 on the other; these were below set trigger of 950 and thus system proceeded to Fail-Safe mode.

Verified to see if I had earlier screwed up on what my lowest TX throttle position readings were; but no, I was getting anywhere from 962 to 965 when throttle was at its lowest position. Then I tried applying some slight pressure on throttle stick and then I was able to go as low as 942 :exclamation:

Conclusion, :bulb: at the flying field we might unknowingly exert more pressure then usual on throttle stick compared to at home while performing radio calibration or setting up Fail-Safe trigger. I have now edited to trigger FS at 925 vice 950 PWM. Try it for yourself you will see different PWM results ( pending stick potentiometer play) if you casually bring down throttle sick to its lowest setting vice constantly holding slight pressure on stick.