The Reasons Why Krakatau Volcanic Ash is Dangerous, Leading to a Series of New Problems

Disruptions caused by the eruption of Mount Anak Krakatau have the potential to evolve into network-wide issues if volcanic activity and ash dispersal persist. The impact is no longer limited to a single route but could spread to numerous airports and other flight paths.

Soekarno-Hottie International Airport holds a vital position in the national aviation network as one of the primary connectivity hubs. When flights at this main hub are disrupted, the delay of a single aircraft can subsequently shift the schedules of subsequent flights.

“If the wind direction changes to the west, the impact could expand to areas such as Halim Perdanakusuma or Bandung. If it moves south, routes to Bali and Lombok must also be monitored. Therefore, the direction of ash dispersal is crucial in determining the extent of the impact,” said the Secretary General of INACA, Bayu Sutanto, to CNBC Indonesia on Tuesday (8/9/26).

A domino effect can occur because a single aircraft typically serves several flight sectors in a day. When an aircraft is delayed on its first flight, the departure schedules for subsequent routes are pushed back, creating congestion at airports.

“Problems in one flight can spill over into the next three or four flights because the same aircraft is used for multiple sectors. As a result, disruptions that initially only occur in the morning can persist through afternoon and evening flights,” said Bayu.

The duration of the disruption is also a critical factor for the industry. If ash activity lasts for more than a few days, the impact may shift from operational issues to demand issues, as prospective passengers begin to alter their travel plans.

“If the eruption and ash dispersal continue for more than three days, the impact could begin to affect passenger confidence. People may postpone trips to Lampung, Banten, or even Jakarta due to the unstable flight conditions,” said Bayu.

International flights are not entirely immune to these risks. Foreign airlines and cargo operators may adjust flight paths when conditions in certain airspace are deemed risky, which could ultimately affect connectivity and logistics costs.

“For international flights, foreign airlines may also avoid the Jakarta FIR (Flight Information Region) if conditions are considered risky. If this persists, the impact could extend to international connectivity, cargo, tourism, and business activities in Jakarta and the affected regions,” concluded Bayu.