Before entering headless mode, make sure the remote controller is directed at the aircraft head. Universal for V911, V912, V913: Toggle both two sticks on remote controller downward and outward for 1 second, LED flckers, then enter the headless mode (Unable to roll, no 100% mode); Universal for: V929, V939, V949, V959, V969, V979, V989, V999, only 100% remote control can enter the headless mode. Toggle both two sticks on remote controller downward and outward for 1 second, LED flckers, then enter the headless mode (allow to roll).