The collection includes the Mariner Mars Orbiter Spacecraft Design Book, design specifications written during the period of 1969-1971. The specifications functionally described the spacecraft construction methods for the Mariner Mars Orbiter '71 project. They provided the spacecraft design based on the environments expected from the time of initial assembly in the Space Assembly Facility through transportation, launch, cruise and orbital operations. The spacecraft and its components, however, did not endure environments beyond flight acceptance levels. The burden of protection was on the operations and facilities rather than on the spacecraft itself. The design specifications also provided ground command capability to backup and update onboard automatic sequences. In addition, this capability was used to initiate the trajectory correction maneuver sequences, to alter or adjust the flight sequence of events, and to select the telemetry data mode that provided the optimum data return. The spacecraft design system requirements described the spacecraft, its support equipment (SE), the spacecraft adapter, the spacecraft system test complex, the spacecraft launch checkout equipment, and all special test facilities required for subsystem and system testing. They also defined the roles of JPL and contractor personnel in relation to the functions of the spacecraft system. The spacecraft design requirements provided full attitude stabilizing in 3 axes, using the Sun and the star Canopus as reference objects. The spacecraft was operated on battery power from launch until solar acquisition was completed, during maneuvers and solar occultation periods. Power was derived from photovoltaic solar cells following the completion of solar acquisition, except during maneuvers. The spacecraft did have two-way communications equipment which permitted transmission of telemetry to the Earth, receipt of command transmission to the spacecraft, and angular position, and Doppler velocity and range tracking by the Deep Space Network for orbit determination. The collection consists of a disassembled one-volume document written by the Spacecraft System Engineer for use by those associated with the Mariner Mars '71 project. It was the basic, accurate and current description of the Mariner Mars Orbiter spacecraft at the system level. It established systems, subsystems and over-all spacecraft design and disseminated design changes to all persons concerned with the program. Arranged in folders as originally sequenced, the files of the collection include cover page, contents, design criteria documents, introduction and distribution lists for written design specifications plus the body of the document. The document includes standard procedures and spacecraft design criteria for requirements and constraints as well as standard trajectories for 1969 through 1971. Arrangement as bound is maintained. Sequenced identification numbers are associated with each folder. Interoffice memos, design specification guidelines, spacecraft functional requirement responsibilities are by the Mariner Mars Orbiter Spacecraft System Manager. He also provided approval for Spacecraft Characteristics and Restraints.
