The Impact on Mission Readiness of Trident On-Board-Repair-Parts Inventory Reductions

Abstract

The feasibility of using a three axis control, momentum bias system with magnetic actuators for sun-oriented operations is explored. Relevant equations of motion are developed for a sun-oriented coordinate system and control laws are developed for: initial spacecraft capture after launch vehicle separation; reorientation from Earth-oriented to a sun-oriented operations mode; sun-oriented attitude control; and momentum wheel control. Simulationsdemonstratingthestabilityandtimeresponsivenessofthesystemareperformed. Sensornoiseinputtests are performed to investigate the systems susceptibility to imperfect conditions. Cross product of inertia effects are also input to test for system instability.

The purpose of this research is to determine the mission readiness impact that would result if the allowance levels of Trident HM&E On-Board-Repair-Parts were reduced by 5%, 10%, 15%, or 20%. The dollar value of the reduced inventories is calculated to estimate the potential cost savings to the Operations and Maintenance, Navy (OM&N) appropriation account. The study concludes that reducing Trident HM&E allowance levels up to 20% wouldhavenoimpactonmissionreadiness. Atthe20%inventoryreductionlevel, the procurement cost savings to the OM&N appropriation for one Trident submarine is estimated to be more than $500,000 per inventory cycle.