Space Shuttle "Backup Flight System, GN&C, Flight Control Program Requirements Document" issued by Rockwell International on October 5, 1979. Comprising over 800 pages, the document is separated by tabs marked "Intro," "Rqmnts," "ADAP," "TDAP," "RDAP," "DDAP," "Jet Select," "RCS Downlist," "Aero PRL," "Util Functions," and "Verification." The document consists of numerous descriptions, tables, lists, and diagrams related to the Shuttle's Backup Flight System, Guidance, Navigation, and Control, and Flight Control systems. In fine condition.