看了楼主和沙发的描述。
正确的遥控器失控保护设置和第5通道没有任何关系,APM遥控器失控保护应由第3通道(油门通道低于975触发),而不是第5通道。
APM官方文档说的很清楚:
If the failsafe clears (throttle climbs back above 975) the copter will remain in its current flight mode. It will not automatically return to the flight mode that was active before the failsafe was triggered. This means that if, for example, you are flying in stabilize mode when the failsafe is triggered