When you start a new career Immelmann, you are eventually taken into the Captain's Room on-base. To the left of the picture is a "cabinet", with 2 sets of 2 "file drawers" below, and an open area with "binder" folders etc. On top of that is a wood-faced radio. Click on that radio face to change all of your Career preference settings. The idea being that the main menu's "Options" are for the Single Missions and Patrols, while there is a separate one for the Careers...
