It seems that every bit of new aviation technology is initially made much more complicated and confusing for pilots to use than is necessary. For example, when GPS navigators first became available, every instructional course from the FAA or others would start out describing the constellation of GPS satellites, their orbital altitude and so on. Who cares? And what, as a pilot, can you do about those satellites anyway?
When GPS approaches were approved we all were bombarded with descriptions of and warnings about RAIM, or the lack of it, at our destination. As I recall, RAIM stands for something like “receiver autonomous integrity monitoring.” It has to do with how many GPS satellites are in view, and their relative angles which can affect the navigation solution. If RAIM is not available, an approach-approved GPS won’t go into the active approach mode. But, again, there is nothing a pilot can do about RAIM.
