Why are the character keys on the Flight Management Computer in alphabetical order? Regardless of which aircraft type and manufacturer, the character keys on any Flight Management Computer are always in alphabetical order, see image: 


From a human factors view, this is sub-optimal, so why? Where does this order come from? 

From chats with pilots I learned that you get used to it easily and can type quite fast with this alphabetical layout, but still, we are all used to the QWERTY or QWERTZ layout...
"we are all used to the QWERTY or QWERTZ layout..." or AZERTY. But which one? Universally there is no one standard, so whichever of these 3 (and others) is chosen, it will be wrong for some users. So the only standard left is simple alphabetic.

Another thing to consider is that the QWERTY-types of layout were chosen to deliberately slow down typists on mechanical typewriters. This slow-down is not necessary on an electronic piece of kit, so the pure-alph format is quite fast once you're used to it.