VMetric Spare Parts Optimization Model Validation.
Abstract
This report describes a study conducted by the U.S. Coast Guard Research and Development Center to determine it VMetric, a spare parts optimization model, can improve the performance of the Coast Guard aviation logistics system. Aircraft spare part stocking levels at the Coast Guard's Aviation Repair and Supply Center (ARSC) are determined using outdated inventory models that overestimate required stock levels. To reduce inventory levels, ARSC obtained VMetric, which determines stocking levels tor spare parts to minimize the cost of inventory while meeting aircraft availability constraints. It can also be used to maximize availability given a cost constraint. The objectives of this project are to validate that the conditions and assumptions under which VMetric provides an optimal solution are met, and to provide a level of assurance that any changes in stocking levels recommended will not result in a reduction in aircraft availability. A simulation model of the logistics system was developed by the Coast Guard Research and Development Center to test the recommended stocking levels without actually testing them in the field. The simulation was validated using historical data and used to compare the performance resulting from using VMetric stock levels to that achieved using historical stock levels. Examination of the VMetric assumptions showed the theory behind the model closely follows that of the Coast Guard aviation spare parts logistics system and provides significant performance improvements. VMetric stock levels provided the same aircraft availability as historical levels with a 34% to 54% reduction in stock position. VMetric improved availability when funding levels for spares remained unchanged. Field tests performed at Air Stations Cape Cod and Astoria support these conclusions.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1997
- Accession Number
- ADA339593
Entities
People
- Christopher M. Rodriguez
Organizations
- United States Coast Guard Research & Development Center