An Analysis and Comparison of Five Water Droplet Measuring Instruments

Five different instruments have been used routinely by the University of Wyoming for aircraft measurements of water droplets. A study has been conducted in which the measurement accuracies of these instruments are analyzed and evaluated. This study includes an analysis of the instruments’ operating characteristics, inherent limitations and calibration errors. Data from these instruments are compared and discussed with an emphasis on the effect of measurement uncertainties. The instruments studied were the Axially Scattering Spectrometer Probe (ASSP), the Forward Scattering Spectrometer Probe (FSSP), the cloud gun droplet impactor, the J-W liquid-water probe, and the CSIRO liquid-water probe.