The U.S. Naval Research Laboratory (NRL) recently developed an airborne Multichannel Synthetic Aperture Radar (MSAR) test bed system consisting of 32 along-track phase centers using two transmit horns and 16 receive antennas. NRL has deployed this system to perform extensive and systematic data collections on a variety of small maritime craft under different collection approaches, subject motions, and environmental conditions. These data collections are detailed in this paper.