Total System Weight and Cost as a Function of Mission Length

1 Total System Weight and Cost as a Function of Mission Length 

Rough estimates [1] for the increase in total system cost and weight as a function of mission duration are summarized in Tables 2.7 and 2.8, respectively. Based on the data presented in these tables, it can be concluded that the constant reliability of the spacecraft power system can be estimated by means of hnear interpolation among the reliability figures that correspond to systems containing whole redundant components. 

2 Reliability Degradation with the Increase in Mission Duration 

Thus far, the emphasis has been placed on the increase in cost and weight as a function of redundant system options. Reliability degradation can occur in spacecraft 

Note These projected values are based on the data collected in the late 1960s for a spacecraft power system. Furthermore, these values show merely a trend in cost factor as a function of various redundant options and mission duration and must not be taken as guaranteed values for other spacecraft or comm unication or reconnaissance satellite. Electrical load requirements are a function of electrical and electronic sensors and devices operating onboard the spacecraft. Additional electrical power is required for attitude and stabilization control mechanisms, which is significantly greater than the electrical power required for onboard electronic sensors and electrical devices. 

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