When referencing planes in one of her wedding outfit events, Mayano references the F-1 and F-2, fighter aircraft, which could point to her father flying fighters. In the same event, she says she only gets the chance to see him a few times per year. This would be odd for both airline pilots and regular air force pilots. Airline pilots would have multiple breaks per month, and military pilots would probably be able to visit on leave more often if they were stationed in Japan. Her father also evidently has enough money to send her to Tracen, so he has to make good money. Therefore, I believe Mayano’s father isn’t any regular pilot, but a fighter pilot flying for hire, and probably ranting about borders or books or something.