 He left Linköping in 1991 after nine years and then completed the Higher Course at the Swedish Armed Forces Staff College from 1991 to 1993.Nilsson then served in the Air Staff's Coordination Department in Stockholm from 1993 to 1995 and as chief of flight operations at Uppland Air Force Wing (F 16) near Uppsala from 1995 to 1997 as well as commanding officer of the wing from 1997 to 1999.In addition to his regular positions, he has also served as "aide-de-camp" to King Carl XVI Gustaf.