The use of object based event driven simulation modelling to assess viable contractor support options

Through the use of an innovative object based support simulation modelling approach, that utilises an ODBC link to combine data generated for a logistic support analysis record (LSAR) with a flexible simulation software product, we are able to easily assess the complexity and content of viable support approaches early in the acquisition phase of the life cycle. Support concept modelling and the use of Monte Carlo simulation is relatively new, however the unique combination of a standard data format (MIL-STD-1388 and DEF STAN 00-60) and a very flexible object based simulation model (eM-Plant) is new. This enables a quick and cost effective means of understanding the various aspects of a potential support solution (spare parts, manpower, support equipment, facilities and associated cost). This event driven approach uses inherent failure rates as the basis for simulation of maintenance activities and timed events for preventive maintenance and operational activities. Within the simulation model, using objects that have been developed specifically for the logistic support simulation requirement, the support situation(s), i.e. maintenance levels, maintenance and support facilities, delay times between levels, spare part pool quantities, supply times and operational plan(s), are constructed. The logistics data, housed in the LSAR data repository, is then incorporated into the model and run through the support situation(s) and operational plan(s) that have been constructed. Within the model the arising of inherent failures result in a ´job card´ that identifies each failure that occurs and the time taken to recover each failure. This time is a combination of delay time and the time taken to perform the various maintenance tasks that are associated with the failure mode within the maintenance plan. By comparison with a deterministic modelling approach the simulated approach provides a more realistic view of when support resources are likely to be required over a period of operational time against planned operational events and activities. Another advantage of this approach is that the object-based software, with objects that have been developed to enable complex support situations to be established, can be easily manipulated to exactly reflect a project specific re- quirement. This differs significantly from more traditional software tools that are fixed in nature and require the users to ´shoe horn´ data and expend effort on the interpretation output information. The object-based software also has the facility to build in optional data such as multiple support concepts, various missions, reliability block diagrams, decision events, etc. All inputs and outputs from the simulation model are in Microsoft Access^® format and the software can link directly to an LSAR to provide information inputs.