This Data Item Description (DID) contains the format and content preparation instructions for the data generated to support operation and maintenance of a system for operations and maintenance personnel and in conjunction with accompanying equipment and subsystem technical manuals. The information shall describe the system in terms of functional signal flow, including operating instructions organized by system operating positions. Maintenance instructions shall include text and illustrative material sufficient to perform system preventative and corrective maintenance. Troubleshooting information shall be sufficiently complete to enable maintenance technicians to isolate fault to the system or equipment (black box) level. System technical manuals shall contain the element of information described in the following paragraphs, supplemented but such illustrative and tabular material as is necessary to support the required data.