Abstract: For the past several years, researchers at NASA Langley have been engaged in a series of projects to study the degree to which existing facilities and capabilities, originally created for work on full-scale aircraft, are extensible to smaller scales –those of the small unmanned aerial systems (sUAS, also UAVs and, colloquially, `drones’) that have been showing up in the nation’s airspace of late. This paper follows an e ort that has led to an initial human{subject psychoacoustic test regardi…