Abstract: This book serves to document the history of the making of Stratospheric Observatory for Infrared Astronomy (SOFIA), a Boeing 747SP carrying a 2.7 meter telescope operating in an open-port cavity. The perspective is primarily from the engineering standpoint, or actually from my perspective. My name is Nans Kunz. I was significantly involved in the development of SOFIA from the beginning; a time span of just prior to the establishment of the SOFIA Study Office in 1985 to about half a year beyon…