Not to throw cold water on a delightful thread BUT
My late husband, A US Air Force officer explained to me the letter-explanation-words were chosen because they are know and/or understood in most of the world's languages.
For example S is Sierra H is Hotel.
Of course the rather ribald humor of militray minds translated Sierra Hotel to "Shit Hot."
There is a NAval Air Station in Nevada (yes Nevada) and the Bachelor Officers Quarters is named Sierra Hotel. Most young bachelor aviator-officers think the name apt. That the Sierra Nevada mountains are nearby evidently let it slip past the censors!