In my fanfic, I always have it that the Flight Control Department covers the bridge officer (as well as their relief/cover), the hangar supervisor, shuttle pilots, hangar/shuttle maintenance techs, as well as specialists attached to the navigational systems (such as VOY's elusive 'astrogation plotter') and deflector. It's never a huge department, but it at least adds a few more redshirts to the crew.
Commander Austin Harris, First Officer, Deep Space Nine (by FltCpt. Bossco)
8.01 - Darkest Before Dawn
(Chapter 8 added, 12/09/2015)