have a sick passenger. specially useful when we are out of the hf range. you also mentioned the engines transmitted data independent of what the pilot is doing. just to say what their p parameters are at the time. the important thing to remember, shutting those systems off, the radio and the acard system off, that is not easily done, it is not an on/off system. if you are going to shut down, we call this box, the fmc, you have to have an intimate knowledge of the architecture of this system. it is not an on/off switch. you have to go in there. it is many key strokes to delete the flight plan. when you put a flight plan in here. it tunes in automatically and