Piyawut Tantimekabut, ATM Expert, Director Level, AEROTHAI, and Chairperson, ICAO APAC ATFM & A-CDM Steering Group, details the progress of Air Traffic Flow Management in Asia Pacific.

Piyawut Tantimekabut, ATM Expert, Director Level, AEROTHAI

In 2015, the ICAO Asia Pacific region adopted a Distributed Multi-Nodal Air Traffic Flow Management (ATFM) Concept of Operations along with implementation expectations continually updated in the Asia/Pacific Regional Framework for Collaborative ATFM.

Rather than unpredictable tactical flow restrictions, ATFM enables orderly cross-border responses to unforeseen disruptions, including weather phenomena such as typhoons, runway surface damage and GNSS radio frequency interference.

ATFM implementation in the region is a mixed bag, however. In the latest ICAO APAC Regional Office survey, published in August 2025, 12 out of 17 States or Administrations (71 per cent) requiring support from others in their ATFM programme reported their implementation status as marginal (70-89 per cent progress) or robust (90-100 per cent progress).

But 11 out of 27 States (41 per cent) not requiring support from others in their ATFM measures reported incomplete implementation (less than 70 per cent progress) while 15 out of those 27 States (56 per cent) have yet to report their status.

The challenges in ATFM implementation are plentiful. There are, for example, known shortcomings on communicating the location of disruptions and the reason why a flight is asked to delay. This results in unexpected reactions, such as flights rerouting around airspace incorrectly perceived as reason for the delay.

“In addition, the region is facing difficulties in maintaining airspace capacity during disruptive airspace events,” says Piyawut Tantimekabut, Chairperson, ICAO APAC ATFM and A-CDM Steering Group and Thailand Member, ICAO ATM Operations Panel. “During large scale weather deviations, there is both a reduction on available altitudes and an increase of required spacing between aircraft, significantly reducing airspace capacity.”

Tantimekabut calls for in-depth ATFM post-operations analyses to fully leverage the results to date. This would allow air navigation service providers (ANSP) to prioritise their investments.

Such data sharing has started among members of the Asia Pacific cross-border Multi-Nodal ATFM Collaboration project (AMNAC), including Southeast Asia, China, Hong Kong SAR and Republic of Korea, but more can be done to enhance operational efficiency. In particular, the ATFM Daily Plan (ADP) should be shared in accordance with ICAO Asia Pacific Regional Framework for Collaborative ATFM, including constraints and expected ATFM measures at international airports, without requiring the signing of agreements.

Tantimekabut also says more instant communication, such as a web conference detailing locations and delay causes, would not only help to ensure appropriate responses but also support other ANSPs’ ATFM programmes that are yet mature.

Longer term, deeper collaboration with meteorological service providers would be beneficial given the increasing prevalence of extreme weather. ANSPs should also pursue better air traffic forecasting to allow for more accurate investment strategies.

Despite the challenges, there are good reasons to be optimistic. In 2024, the ICAO Air Navigation Conference (AN-Conf/14) agreed to transition to the Flight and Flow – Information for Collaborative Environment (FF-ICE) by 2034. FF-ICE allows stakeholders to collaboratively and accurately negotiate trajectories to achieve an optimal outcome for all involved parties.

“In addition, communicating flight and flow information through system-wide information management (SWIM) rather than traditional messaging that relies on specifying recipient addresses ensures that information will be delivered automatically and in a timely manner to authorised users,” says Tantimekabut.

In parallel, the application of Machine Learning (ML) / Artificial Intelligence (AI) presents an exciting opportunity to further enhance the accuracy of trajectory prediction, thus improving ATFM operations.

Ultimately, the integration of FF-ICE and ATFM processes will enable ANSPs to achieve more accurate trajectory and traffic demand predictions. This, in turn, will support the improved scaling of airspace and airport capacity while maintaining or even reducing ATFM delay.

This will allow stakeholders to automatically process the information in ADP

Transitioning flight information towards FF-ICE via SWIM also provides the possibility of digitising the ADP, moving away from PDF e-mail attachments.

“This will allow stakeholders to automatically process the information in ADP and gain deeper insights into whether the flights are expected to operate through airspace or into airports with a demand-capacity imbalance, and to understand the nature of that imbalance,” adds Tantimekabut.

To ensure continued progress, at the regional level, an ATFM Concept Ad-hoc Group was established under the ICAO Asia Pacific ATFM and A-CDM Steering Group, with the target of delivering a revised Regional ATFM Concept of Operations in 2027. In parallel, a similar activity is ongoing under the Asia Pacific ANSP Committee (AAC) to support the region’s efforts to increase capacity.

Piyawut Tantimekabut, ATM Expert, Director Level, AEROTHAI

Globally, ICAO recently released a State Letter seeking comments on the proposal to amend Annex 11 and PANS-ATM (Doc 4444, which calls for States to support other States’ ATFM programs, with envisaged applicability in November 2030. The proposed change will be accompanied by a revised ICAO Manual on Collaborative ATFM (Doc 9971), being revised through the ICAO ATM Operations Panel.