Use of equipment health monitoring information for assessing potential exposure to volcanic events

The eruption of Eyjafiallajokull early in 2010 led to major disruption to UK and European airspace with the grounding of many aircraft, the main concern being the harmful effects of volcanic ash deposits on engine components and other aircraft systems. Advice from engine and airframe OEMs is to avoid visible ash. However, there will be times when ash is not visible or an area of ash is inadvertently entered. Although the UK Meteorological Office provided estimates of geographic location and density for given time periods, no existing mechanism was available to reliably establish likely exposure to ash particles.

This paper provides an overview of techniques developed at that time to fuse standard equipment health monitoring (EHM) data, routinely collected at the end of each flight, with meteorological information, generated by external agencies, for the purpose of identifying potential exposure to ash particles. Hence, having an EHM system that may be able to identify potential exposure will mitigate the risk of undetected engine damage. The paper also contains a brief explanation of volcanic ash and its effect on gas turbine engines, as well as a review of recent volcanic activity and corresponding eruption magnitudes.