Volcanic Events of Importance

Though it may come as a surprise to many, 10 to 20 volcanic “events of impor­tance” occur globally every month.

On a recent consult­ing assign­ment, I learned that volcanic ash in the atmos­phere can cause real problems for airplane engines, and the airlines must balance safety and efficiency in response to these events. The goal from a safety perspec­tive is to avoid aircraft encoun­ters with volcanic ash. From the perspec­tive of efficiency, the  goal is to minimize re-routing of aircraft.

Because of this, the International Civil Aviation Organization (ICAO) coordi­nates the activ­i­ties and opera­tions of nine Volcanic Ash Advisory Centers (VAACs) in strate­gic areas around the world. These centers produce advisory infor­ma­tion about volcanic ash and its presence in the atmos­phere used by airlines in flight planning and air traffic control to warn in-flight aircraft.

Because normal aviation radar is ineffec­tive in locat­ing volcanic ash clouds, the VAACs detect eruptions and forecast how the ash is going to disperse in the atmos­phere. Standard advisories include eruption location, the specific volcano produc­ing the event, wind speed and direc­tion and, most impor­tantly, flight levels affected by the ash so that aircraft en route or sched­uled to depart can be advised to fly well above or around the affected area.

These Airways Volcano Watch facil­i­ties operate much in the same way that airport fire services are maintained — in constant readi­ness but with the hope that they will rarely have to be used.

Checkout the 2008 eruption of gas from Kilauea in Kauai, Hawaii: