| Popis: |
Air Force plans for future spacelift feature the development of a Reusable Booster System (RBS) to achieve lower flight cost and increased operability. It is expected that the inclusion of Integrated System Health Management (ISHM) will result in significant improvement in the system’s capability to achieve these goals. The present study develops and assesses the ground operations segment for two variations of an RBS vehicle; one which includes ISHM and one which does not. The investigation is conducted using a Lockheed Martin developed flexible discrete-event simulation model for RBS operations analysis. Metrics employed during evaluation include turnaround time, call-up time, and maintenance labor hours per sortie. The model permits Monte Carlo simulation of probabilistic events, resolution of resource contention among parallel processes, determination of need for task performance in a given cycle, and ensures predecessor tasks are completed. Additionally, the model enforces constraints arising from hazardous operations, access, space limitations, and available resources. Given that high variability in task time completion is an inherent feature of launch vehicle processing, task durations are calculated using uncertainty and variability distributions. Simulation results indicate a 34% reduction in turn time hours and a 38% reduction in turn time labor with the inclusion of ISHM capabilities. ISHM-generated knowledge of internal component states results in a reduction of required inspection and needless disassembly operations increasing Operational Responsiveness. ISHM-enabled reductions in call-up time were more modest with a 3% improvement in call-up time and labor versus the No-ISHM RBS system. Additional results indicate that operations tasks such as main engine servicing, commodity loading, structural inspections, and lift and mate operations rank among the longest operations tasks and drive the system turn time. The scope of the present investigation was strictly for nominal ground operations that occurred from horizontal landing through vehicle launch and the results indicate a clear operational advantage for the inclusion of ISHM for RBS. Additional ISHM benefits are expected for flight operations, mission success, and contingency scenarios in either flight or ground segments and would be the recommended direction for additional investigation. |
