<p>Keep in mide, the air force is made of PEOPLE…therefore individual cases are looked at, as shocking as that is. So, contradictions to rules that seem set in stone is possbile and probable.</p>
<p>Also, keep in mind that these may change for aircraft. For example, glasses in a F-15 would probably not be a good idea so much with 8 G turns…but I doubt a C-17 or C-21 needs to perform maneuvers that are going to take the glasses off your face that often.</p>