Two observations, one mundane, one serious.<p>Funny how even in reference textbooks on radio/EM/etc, for some reason people cannot help but use half circles on a plot about a sine function, instead of the proper function shape. Don't know why that is! See Figure 1-2.<p>And more seriously, I think that all of our useful military education texts date from pre-1990s, when the military was one part an able research and development (and educational) and contracting institution. Now today most all of that capability has been outsourced to the military contractors and anyone who could write such a text (or properly design an aircraft on the military side) has long left.