The 3-D National Radar Mosaic is a product from NSSL which combines base data from the approximately 130 NEXRAD sites to a 1 x 1 km horizontal and 31 vertical level resolution Cartesian grid. During the winter of 2005, icing research flights were flown over Ohio and nearby states by various aircraft. Analysis of the mosaic reflectivity data with flight data co-located in space and time suggest that it is possible to provide valuable information about the presence of in-flight icing hazards caused by supercooled liquid droplets with just radar reflectivity alone. This can be accomplished by determining a threshold reflectivity value below which it is likely that mostly smaller particles are present. Dominance of smaller particles appear in the mosaic as reflectivity gaps, depressions and sharp vertical and horizontal gradients in reflectivity and tend to be associated with higher liquid water contents. The use of the reflectivity threshold as well as pattern recognition software could provide upgrades to NCAR's Current Icing Product (CIP) for the detection of in-flight icing hazards. Several examples using combinations of NEXRAD 3-D mosaic and research aircraft data will be presented to illustrate the possible utility of this method.