I'm not in the aviation industry, but I've had several junior staff and more recently, students, who have completed a degree and then decided to get into a different field of work. I have to say that it's an area that's interesting, reasonably well payed and enjoyable if you're the right type of person and enjoy hard physical work, but it doesn't require a degree. Without an exception that I can think of, they have enjoyed their work, and their degree, whether in the humanities or sciences, has not hindered them.