Anak Krakatau eruption grounds 209 flights across Indonesia's eight airports

On Sunday, Indonesia's aviation system came to a halt. Eight airports, including Soekarno-Hatta International near Jakarta—the country's main international gateway—suspended all flight operations. The cause was an ash cloud drifting from Anak Krakatau, a volcano sitting in the strait between Java and Sumatra, which had erupted violently the day before. By the time authorities announced the closures, more than 22,000 passengers were stranded, and 209 flights—both domestic and international—had been cancelled or delayed. The airport operator, Angkasa Pura, extended the shutdown repeatedly throughout the day, keeping the facility closed to traffic until at least 9:30 p.m. local time.

The eruption itself had been dramatic. On Saturday, Anak Krakatau expelled lava and produced booming sounds so loud they were heard 700 kilometers away, according to Indonesia's geology agency. The ash column climbed to 20,000 feet on the Java side of the volcano and reached 15,000 meters on the Sumatra side, spreading across parts of Banten province. Two additional eruptions occurred on Sunday, keeping the threat active and the airspace around Jakarta hazardous. Volcanic ash is not merely an inconvenience to aviation—it damages jet engines by baking onto hot internal components and wearing out turbine blades, clogs fuel and air systems, and can scratch pilots' windscreens, creating serious safety risks.

The disruption rippled far beyond the airport terminals. Singapore Airlines cancelled all its flights to and from Jakarta for the remainder of Sunday. Qantas reported disruptions to multiple services, including cancellations on the Jakarta route, and issued a statement emphasizing that safety remained the priority while their meteorologists and operations teams monitored conditions. International routes to Doha, Sydney, and Kuala Lumpur were affected. Domestically, at least 16 flights to Bali were scrapped. The transport ministry confirmed the scale: more than 22,000 passengers caught in the disruption.

On the ground, the ash caused immediate harm. Students and residents in nearby areas suffered eye irritation severe enough that several schools cancelled activities on Saturday. Fishers, unable to work safely or at all, cancelled their trips, disrupting livelihoods that depend on daily access to the water. Local media outlet Kompas documented these cascading effects across the region.

Indonesian authorities moved quickly to address the crisis. The disaster mitigation agency, BNPB, announced plans for weather modification operations, including cloud-seeding to trigger rainfall that could wash the ash from the air. Lt Gen Suharyanto, the BNPB chief, told reporters at a press conference that if rain fell heavily enough, the volcanic ash that had been disrupting daily life since Saturday would be cleared rapidly. Port authorities also issued restrictions: ships passing through the strait were prohibited from approaching within two miles of the volcano and were ordered to remain vigilant.

Anak Krakatau—the name means "child of Krakatau"—has been intermittently active since it emerged from the sea in the caldera left behind by the catastrophic 1883 eruption of Mount Krakatau. That earlier eruption killed approximately 35,000 people and remains one of the deadliest and most destructive volcanic events in recorded history. The current volcano, though far smaller, sits in one of the world's busiest shipping lanes and near one of Southeast Asia's most important aviation hubs, making even modest eruptions consequential for millions of people and billions in commerce.