Return to Home (RTH) is the function by which the drone automatically flies back to its recorded home point. It can be triggered in three ways: manually by the pilot, by the system on low battery, or automatically when the control link is lost.
Before flight, verify that the home point has been recorded correctly and that the RTH altitude clears every obstacle on the return path. A wrong RTH altitude is a classic cause of collisions — the drone flies home in a straight line and hits a tree or a building.