Widespread Effects on Aviation of the 2008 Eruption of Chaiten Volcano, Chile

The 2008 eruption of Chaiten in southern Chile was the first eruption to pose widespread hazards to aviation in southern South America since the VEI 5 eruption of Chile's Cerro Hudson in 1991. Five encounters of aircraft with volcanic-ash clouds occurred in the week following the start of the eruption on 2 May 2008; three of these encounters occurred at low altitudes (less than 2 km) near the airport in Bariloche about 225 km from the volcano and involved significant engine damage. An airline company in Argentina reported that turbine damage from one encounter cost USD 2.5 million to repair. Operations at 16 airports in Chile, Argentina, and Uruguay at distances up to 2300 km from Chaiten were disrupted by flight cancellations or airport closures. The airport in the town of Chaiten, located about 15 kilometers from the eruptive vent, was severely damaged by ash fall and secondary lahars and is closed for the duration. Bariloche airport was closed for nearly four weeks in May and June 2008, during the start of the region's busy ski season, because of continuing concerns about the possible presence of ash in the surrounding airspace. Cancellation of 158 flights to Bariloche in May resulted in loss to an airline of USD 0.7 million. From the beginning of the eruption, advisories to aviation about the presence of ash in the atmosphere were issued by the Buenos Aires Volcanic Ash Advisory Center (VAAC), one of nine VAAC worldwide established by the International Civil Aviation Organization. Aviation meteorological offices and civil aviation agencies used the VAAC advisories as the basis for formal volcanic-ash warnings to airline operations centers, pilots, and air-traffic control centers. The Buenos Aires VAAC worked to improve its operational capabilities for ash-dispersion forecasting and also coordinated its advisories with the adjacent Toulouse VAAC when ash clouds moved into airspace over the Atlantic Ocean.