Integrated Icing Diagnostic Algorithm Meteorological Evaluation

Aircraft icing has long been identified as a major safety hazard for the aviation community. To mitigate the dangers associated with aircraft icing, the Federal Aviation Administration (FAA) Aviation Weather Research Program (AWRP) has sponsored research and development activities aimed at providing timely and accurate icing detection and forecasts for the aviation community. Utilizing AWRP funding, the Research Applications Program at the National Center for Atmospheric Research (NCAR/RAP) has developed the Integrated Icing Diagnostic Algorithm (IIDA).

IIDA uses output from the Rapid Update Cycle, GOES-8 satellite imagery, NEXRAD mosaics, and National Weather Service surface observations to produce three-dimensional grids of Icing Potential, Supercooled Large Drop Potential, and Icing Type.

In order to assess the operational effectiveness of the IIDA, the FAA William J. Hughes Technical Center (WJHTC) Communication/Navigation/ Surveillance Engineering and Test Division, Weather Branch (ACT-320), performed an event-driven, region-specific, qualitative evaluation of the IIDA during the late-winter, early-spring season of 2000. The evaluation involved comparing IIDA output for aircraft flight routes in the Northeast, Midwest and Inter-Mountain West regions of the United States to other data sources that indicated the likelihood of icing conditions. The evaluation resulted in the identification of strengths and weaknesses of the IIDA product in relation to specific geographic regions of the United States. Results obtained will be applied to the future development of the algorithm.