Unmanned aircraft systems (UAS) can provide significant enhancement to capability, when used in a manner best aligning inherent design characteristics to requirements of a given application. However, wide variability in designs, configurations, and operational attributes requires the performance of thorough investigation to appropriately identify suitable platforms. Failure to perform sufficient examination can lead to expensive cost overruns, diminished capability, and degraded safety. Assessing the capabilities and performance associated with categorized UAS platforms through experimentation and analysis can produce valuable insight regarding propriety for application. The use of modeling and simulation (M&S) provides the means to identify limitations, benefits, and considerations necessary to aptly employ UAS. Understanding how to best select, configure, and apply this rapidly advancing technology is anticipated to support increased innovation, safety, efficiency, and effectiveness; elements essential to achieving successful integration into the National Airspace System (NAS) for use across government, industry, and academia. This paper contains a description of continued work from an experimental research project featuring use of M&S to identify, observe, and investigate critical factors of UAS platform application in an efficient and expedient manner. Operational design attributes (i.e., published and derived metrics) of 282 commercially-off- the-shelf (COTS) platform configurations were identified, classified, and analyzed to create category representative UAS performance models. These models were employed in 30 experimental trials and subsequent statistical analysis. The results led to the development of a theory of operation, selection requirements for use of UAS in aircraft rescue and fire fighting (ARFF), and an expanded series of UAS category performance models. Future anticipated research, including improvement of performance models, expanded simulation trials, and further refinements will also be discussed.