Detecting high-altitude ice

High-altitude icing is a serious threat to aviation safety, and especially affects engines. Systems able to detect and help aircraft avoid the dangerous atmospheric conditions will help improve safety.

Providing such systems is the EU-funded HAIC (High altitude ice crystals) project. The exceptionally large consortium includes 34 European partners plus 5 from Australia, Canada and the United States. Main goals are to provide ice particle detection systems for enhanced aircraft safety, and to help the industry comply with anticipated new regulations.

The group has addressed 18 technical objectives concerning development of suitable systems. The partnership runs for four years from mid-2012 to mid-2016.

Second-year work involved selection of the most sophisticated probes for the first international field campaign, which were later installed on a research aircraft. Instruments supporting calibration of the test facilities were also selected and evaluated.

The first field campaign was conducted successfully in early 2014, and utilised the MET-FR RDT device for detecting thunderstorm convection. Analysis of all campaign data is on schedule.

Researchers assessed the project's capability to judge icing conditions using satellite data. Feasibility testing was also conducted on HAIC's detection systems and weather radar. Five of eight candidate technologies were selected for flight testing.

The team developed devices able to create ice crystals with specific sizes and other properties, to be used for testing. A calibration methodology was also created and shared with the international community. Finally, the group has completed laboratory testing of ice crystal trajectories and related phenomena, data from which led to the creation of preliminary mathematical models.

HAIC is producing a thorough understanding of icing conditions, to be incorporated into effective aviation warning systems. The expected result is improved aircraft safety, with a bonus of commercial possibilities for European business.