Much like the multirotor version of Ardupilot, fixed wing (Arduplane) has an autotune mode. It works very differently from the autotune of the multicopter. Before we get into the specific details of autotune for fixed wing, let's take a look at how flight modes in Arduplane work.
You'll recognize many of the flight modes in the Arduplane interface from Arducopter. However, many of them work quite differently. And that's understandable. After all, a fixed-wing aircraft must keep moving to keep aloft. Here is a summary of the fixed-wing flight modes:
MANUAL: Consider this making the airplane dumb. In this mode, Pixhawk's features are essentially off. You're flying the airplane as you would any other RC aircraft.
STABILIZE: This mode offers basic stabilization. You're still flying the plane on manual control, but Pixhawk will make minor corrections for turbulence and wind. Also, upon releasing the sticks, the airplane will level itself out.
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