Generate a correct and concise answer for the question based on the words in the context.

Context : F 13 Norrkoping, Bravalla Flygflottilj, Bravalla Air Force Wing, or simply ''F 13'', is a former Flygvapnet - Swedish Air Force - wing with the main base located near Norrkoping in south-eastern Sweden.
Question : What military branch did F 13 Norrkoping belong to?
Swedish Air Force