A Continuing Investigation of Diurnal and Location Trends in an Ice Crystal Icing Engine Event Database 2019-01-1964

Due to ongoing efforts by the aviation industry, much has been learned over the last several years regarding jet engine power loss and compressor damage events caused by the ingestion of high concentrations of ice crystal particles into the core flow path. Boeing has created and maintained a database of such ice crystal icing (ICI) events to aid in analysis and further study of this phenomenon. This article provides a general update on statistics derived from the Boeing event database, and provides more details on specific event clusters of interest. A series of three flight campaigns have, over the past five years, collected in-situ data in deep convective clouds that will be used for the assessment of the new FAA CFR Part 33 ice crystal environmental envelope Appendix D, and the equivalent EASA CS-25 Appendix P. The most recent Boeing engine event study in 2015 focused on oceanic cloud systems that caused events in Southeast Asia, a region expected to have similar cloud properties as the first flight campaign in Darwin, Australia. The current study will examine ICI engine events over South America and Africa, which are caused by large deep convective continental clouds of the type that were not the main focus of the three Appendix D/P flight campaigns. Continental event clouds are compared to the previously studied oceanic event clouds, in order to ascertain whether any systematic differences exist that should be considered when assessing the representativeness of the flight campaign datasets. The results may also be useful to those developing nowcasting algorithms identifying high ice concentration regions using satellite measurements.