We developed a compact, ultra-wideband radar demonstrator for measurements of snow thickness. We designed the radar to be capable of reconfigurable operation over Ku- and S/C bands, and with a size, weight, and power compatible with a C-3 class unmanned aircraft system (UAS). We implemented the radar’s radio frequency frontend using low-cost laminate materials and employed 3D printed antennas for an inexpensive implementation. To demonstrate its performance and capabilities, we first conducted a series of laboratory tests, followed by tests of opportunity in Antarctica using a sled-based setup. Next, we integrated the radar demonstrator into an Aurelia X6 Pro system and completed a series of local flight tests over areas including grass-covered land and a wooded section with different seasonal foliage conditions. Lastly, we used our UAS-borne radar test bed to map seasonal snow accumulation to a depth close to ∼30 m in Greenland from 100-m altitude. In this paper, we offer a succinct description of the radar test bed electronics, a discussion of laboratory tests and integration considerations, and present sample results from various field scenarios.