回答“On and off switch”You should get a tactile switch click when you push it. If not, there is the issue. If there is no tactile click and the switch itself feels "mushy", then the likely issue is the switch button finger has slipped underneath the switch. It is a simple, but fiddly repair. take the battery out, remove the black cover underneath the battery. Take the cockpit cover off. Next you need to get the main PCB lifted up. This can be done carefully by taking the mounting screws out. Removing the camera will make it a little easier, but putting the camera back is a bit harder. If the camera assembly is left on, you just can't lift the PCB up as far. BE EXTRA CAREFUL AND DON'T FORCE IT. All you really need to do though is to lift the back of the PCB up a little bit, and carefully pull the switch backwards using a fingernail or similar. Set the PCB back down and see if you can feel the switch. If so, reassemble it carefully keeping the PCB pushed down until you get some screws back in it towards the back. If you resorted...