Prioritizing Repair, Modification or Replacement of Space Launch Ground Support Equipment Designated as WorstCase Actors

摘要

Within the reliability, maintainability and availability (RMA) arena of space-related engineering, a “worst caseactor” is defined as any range asset that warrants further analysis in order to identify the root cause of the asset’sdeficient or costly performance. The evaluation of worst case actors (WCAs) in Space Launch Operations GroundSupport equipment takes into account a multitude of criteria. The criteria may include, but is not limited to itemssuch as number of regular and emergency depot level maintenance actions; number of failures; performancecriticality; safety criticality; number of repairs; mean time before failure (MTBF); mean time to repair (MTTR);average down time; acquisition cost; sustainment cost; repair cost, spares on hand; vendor support and others. Oncea piece of equipment, line replaceable unit (LRU) or system is identified as a WCA, the question arises as towhether or not the item should be prioritized into the budget for immediate repair, modification, or replacement. Theanswer to this question can be facilitated through the use of qualitative risk assessments. A qualitative riskassessment can highlight potential candidates for immediate repair, modification, or replacement by determining thelikelihood of an item failure and the potential consequence to the system should the failure occur. The key inassessing the need for immediate repair, modification or replacement of an identified WCA is to ascertain whichcriteria to utilize in the qualitative risk assessment. The determination as to prioritization of an identified WCA canbe achieved through analysis of an items likelihood of occurrence and consequence of occurrence.