Accession Number : ADA261470


Title :   An Evaluation of Macro Methodologies Used by OSD and the United States Air Force to Estimate: Acquisition Support Funding for New Aircraft Systems


Descriptive Note : Final rept.


Corporate Author : LOGISTICS MANAGEMENT INST BETHESDA MD


Personal Author(s) : Wallace, John M


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a261470.pdf


Report Date : Jan 1992


Pagination or Media Count : 92


Abstract : This research evaluates Initial Spares estimating methods used by OSD and the Air Force. Two macro estimating approaches were studied: factor based approaches that use historical percent of flyaway cost to estimate Initial Spares funding for new aircraft and the Logistics Support Cost (LSC) model - a detailed build-up method that uses aircraft equipment and operational characteristics to estimate Initial Spares. Findings: (1) Factor based approaches ignore important considerations that affect the requirement for spares. Historical Initial Spares requirements must be adjusted to reflect new budget definitions and revised Air Force computational procedures as well as the operating tempo, equipment configuration, reliability, and operational availability of the new system. LMI demonstrates an improved approach that makes these adjustments. (2) The LSC model version 2.2 closely approximates requirements calculated using the Air Force D041 system. However, the model is very sensitive to the accuracy of input variables such as Mean Time Between Removal - variables that have significant uncertainty. Procedures used to estimate subcomponent requirements have not been validated. An approach is suggested to improve the subcomponent estimates.


Descriptors :   *COSTS , *COST MODELS , *LOGISTICS , INPUT , REQUIREMENTS , UNCERTAINTY , LOGISTICS SUPPORT , AIR FORCE , REMOVAL , AIRCRAFT , ACQUISITION , APPROACH , MEAN , BUDGETS , LIFE CYCLES , AIRCRAFT EQUIPMENT , LIFE CYCLE COSTS , CONFIGURATIONS , AVAILABILITY , RELIABILITY , MODELS , AIR , ACCURACY , CYCLES , ESTIMATES , TIME , VARIABLES


Subject Categories : Economics and Cost Analysis
      Logistics, Military Facilities and Supplies


Distribution Statement : APPROVED FOR PUBLIC RELEASE