mattpilot said:@BD King...
The first time i've seen it, or anybody else in my CFI class, was when we opened the CFI test prep.
It doesn't pop up anywhere else (not to my knowledge). The basics of using geometry and vectors to figure out what wind does to an airplane, isn't hard. Its this stupid thing the FAA came up with and the way it goes about explaining/illustrating it that confuses me - and apparently, i'm not the only one.
After looking over it more, i am starting to understand it better - but if asked on the CFI checkride, i would in no way explain it the way the 'book' does. There are simpler ways of going about it.
The 'Pilot's Handbook of Aeronautical Knowledge' explains the theory and use of the wind triangle. I found it quite usefull for reinforcing the basic concept of how wind affects navigation. The wind side of the E6B is just a kind of graphical representation of the wind triangle.