Engine Ground Demonstration test approach

The hardware portion of the current phase of the Integrated Solar Upper Stage (ISUS) program culminates in a system ground demonstration test. The potential application of ISUS technology to a wide array of future missions complicates the process of selecting from among demonstration system design options and test approaches. The approach to this system demonstration has been to maximize system technology readiness level for the entire array of potential missions within the constraints of the program. To this end, system design and test operations planning has been carried out with a premium on demonstrating those elements of the system common to all missions. In addition, test planning has been managed to allow a margin for testing those portions of the system envelope needed to confirm acceptable operation for scenarios within the mission set that are specific to a given mission or mission type. Examples drawn from the specific Engine Ground Demonstration (EGD) design selections are used to illuminate this approach, with the result that the EGD system design is not only described, but the reasons for its particular characteristics are made evident