You don't want "someone who knows about aviation" you want someone who knows how to run a successful organisation!
The CEO needs to know just enough "aviation" to understand what she does NOT know about aviation. Her job is to create the conditions under which her people can succeed in what they are supposed to do.
Paraphrased from a very clever and brave acquaintance who went all the way from being a programmer to a directorship of a major Australian bank.