, headless mode means that the quadrotor’s reference for direction will be it’s takeoff (binding) direction, and not it’s current direction.
For example, in headless mode if you push the aileron stick (the right stick on the most of the transmitters) backwards towards yourself, the quadcopter will start flying towards you. In normal mode the quadcopter would start flying in the direction of it’s own backside.
behind headless mode is that quadcopters can be hard to control, and beginners can lose the orientation easily, even if the quadrotor has color-coded propellers, or different colored LEDs in the back and in the front.
To address this issue and make quadcopters easier to handle, manufacturers have added a magnetometer (a compass) to the electronics of the quadcopter. When you start your quadrotor and bind it with the transmitter, the compass is initialized, and your drone will take note of this initial direction.
When you activate headless mode, the quadcopter will recall this initial direction, and will start using this as the “forward” direction. So when you push the aileron stick to the left, the quadcopter will start moving inyour left direction, right will become your right direction. Pushing the aileron stick forward will move the quadcopter forward away from you,while pushing it backward will bring it back towards you.
To fully utilize headless mode, it’s important to start the quadcopter facing away from you – this way you can be sure the headless mode’s directions will match your stick directions.
Headless mode does not change how yaw or throttle works, as their behavior do not depend on the drone’s orientation – for example turning left will always stay turning left, only moving left changes.
The one key return function
simply means that the quadcopter will start flying backwards in your direction, as if you pushed the aileron stick backwards in headless mode.
It’s important to note that neither headless mode, nor one key return uses a gps or radio signals for orientation, so the quadcopter will not know where you are, it will simply fly backwards. For example if you activate one key return (or use the back direction on the aileron stick), and the quadcopter is on your left, it will fly past you on your left side.
If you are a beginner, headless mode can be useful for a first drone.However if you already fly well, headless mode will probably not improve your flying.
For headless mode support check out these quadcopters: