A simulation of the I3 to D repair process and sparing of the F414-GE-400 jet aircraft engine

Abstract

The F/A-18E/F is the latest multi-mission tactical aircraft to enter United States Naval Service. It generates power via two F414-GE-400 engines, each of which is composed of six modules. In addition to a new aircraft model and engines, a new concept, the I3 to D Repair Process, is being used for F414-GE-400 module and engine repair. In the I3 to D Repair Process, the intermediate level no longer repairs modules. Instead, the depot level performs all module repairs. This thesis develops and exercises a simulation of the I3 to D Repair Process for the F414-GE-400 by incorporating simulated F/A-18E/F flight schedules and engine failures to populate the repair cycle. The simulation provides operational availability (A0) and probability to spare the repair process given an infrastructure and sparing profile. Three previous years of module failures and depot repair times are used to calibrate the model. Simulation results for the baseline studied showed the distinct influence of certain input parameters. Aircraft service entry time had only a relative short-term effect on A0. Cannibalization of engines among F/A-18's improved A0. Scheduled maintenance dramatically impacted A0. Finally, of all the components of depot repair turn around time (RTAT), "In Work" and "Other" influenced A0 the most. The simulation was also used to examine the impact of varying build windows and depot RTAT. It allows easy changes of input parameters to be made so that a multitude of effects on A0 and probability to spare the repair process can readily be studied.