Task: Question Answering
Input (English): Context : F 13 Norrköping, Bråvalla Flygflottilj, Bråvalla Air Force Wing, or simply ``F 13'', is a former Flygvapnet - Swedish Air Force - wing with the main base located near Norrköping in south-eastern Sweden. 
Question : What military branch did F 13 Norrköping belong to?
Output (English): Swedish Air Force