The significant problem of engine power-loss and damage associated with ice crystal icing (ICI) was first formally recognized by the industry in a 2006 publication [1]. Engine events described by the study included: engine surge, stall, flameout, rollback, and compressor damage; which were triggered by the ingestion of ice crystals in high concentrations generated by deep, moist convection.
Since 2003, when ICI engine events were first identified, Boeing has carefully analyzed event conditions documenting detailed pilot reports and compiling weather analyses into a database. The database provides valuable information to characterize environments associated with engine events. It provides boundary conditions, exposure times, and severity to researchers investigating the ICI phenomenon. Ultimately, this research will aid in the development of engine tests and ICI detection/avoidance devices or techniques.
This paper first provides a detailed examination of the ICI engine event database from a statistical perspective. Environments sampled during the 2014 HAIC-HIWC field campaign, based in Darwin, Australia, are compared to the ICI engine database and it is shown that test flights fell within the expected range of conditions. A new, novel approach to track mesoscale motion of convectively generated ice is introduced. The Mesoscale convective Ice Following (MIF) model uses infrared satellite (IR) cloud top data in conjunction with vertical wind profiles in an attempt to improve upon the detection of high ice water content (HIWC) regions embedded with mesoscale convective systems (MCS). Finally, a preliminary assessment is made of MIF model results using in-situ ice concentration measurements for verification.