Jakarta’s Soekarno-Hatta International Airport will cut aircraft throughput from a current peak of 72 movements per hour to around 60 per hour because of a shortage of air traffic control (ATC) staff.

Indonesia Transportation Ministry director aircraft operations Muzaffar Ismail said that “a high frequency of flights [brings] a greater risk of collisions and accidents” at the capital’s main airport.

Soekarno-Hatta was rated the world’s eighth busiest in 2014, with a passenger count of 62.1 million for the year. The airport’s chronically congested two-runway infrastructure was originally designed to handle 22 million passengers per year.

National airport operator PT Angkasa Pura II has plans to expand the airport with new and revamped terminal capacity, as well as build another runway.

The airport is also scheduled to open Terminal 3 Ultimate in 2016, which will add capacity for another 25 million passengers per year.

To cope with the newly proposed reduction in movements/hour, the airport will extend its operating hours to maintain overall passenger numbers.

Carriers such as Garuda Indonesia have mooted a possible switch to widebody aircraft for domestic flights to keep passenger throughput numbers up.

“There is a possibility we could operate widebody aircraft on domestic flight routes such as from Jakarta to Surabaya, Medan, Denpasar, Balikpapan and Makassar,” Garuda Indonesia CEO Arif Wibowo said. He added the carrier would assess each route on its merits, and “synchronize the airline’s capabilities with the available capacity.”

Earlier this year, FAA reported that a proposed promotion of Indonesia from Category 2 to Category 1, originally scheduled for mid-2015, would likely be delayed.

“The Indonesian government is on the right track,” FAA’s Southeast Asian spokesperson, Donald Ward, said earlier this year. “But in our view, the [original] target time is too short because of the work involved,” he added.