Performance of the forward scattering spectrometer probe in NASA's Icing Research Tunnel

Two Forward Scattering Spectrometer Probes were used to measure droplet distributions in the NASA Lewis Icing Research Tunnel. The instruments showed good agreement when the median volume diameter (MVD) was approximately 16 micrometers. Coincidence events affected much of the data and caused the measured MVD to be about 2 to 3 micrometers larger than expected. Coincidence events were reduced by shutting down half of the spray bars in the tunnel during certain tests.