New tool to ensure safe aircraft separation being tested in S’pore, with AI planned for next phase

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The current prototype of the air traffic control tool automates the process of determining the time and distance needed for two aircraft to depart safely one after the other.

The current prototype of the air traffic control tool automates the process of determining the time and distance needed for two aircraft to depart safely one after the other.

ST PHOTO: STEPHANIE YEOW

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  • CAAS and MITRE are developing a new tool for Singapore's next-gen air navigation system to automate safe aircraft departure timing.
  • The tool will provide controllers a 'rundown clock' to confirm optimal take-off times, boosting runway capacity and improving safety and efficiency.
  • Human controllers currently rely on manual calculations for aircraft separation due to 49 permutations.

AI generated

SINGAPORE – A new air traffic control tool that can ensure safe separation between aircraft is being put through the paces in Singapore, and it will be given AI capabilities in future as part of the next-generation air navigation system here.

The current prototype automates the process of determining the time and distance needed for two aircraft to depart safely one after the other.

It is being developed by the Civil Aviation Authority of Singapore (CAAS) and research and development laboratory MITRE Asia Pacific Singapore.

The Straits Times

had previously reported

that the next-generation air navigation system will be rolled out in the second half of the 2020s.

The tool will provide a countdown of the exact time gap required to prevent collisions and manage wake turbulence — the air disturbances generated by the preceding aircraft – between two aircraft that depart consecutively.

It will compute the required time needed to maintain a minimum vertical and horizontal distance between two aircraft, right as the first aircraft of the two takes off from the runway.

A “rundown clock” – or the visual countdown – will be shown to the air traffic controllers in the control tower, said Mr Vincent Hwa, director of air traffic services at CAAS.

The air traffic controllers can then allow the second aircraft to take off once the countdown reaches zero, providing them with “safety assurance” and allowing them to authorise aircraft to take off at the “most optimal moment”, he added.

This will maximise capacity on the runway and in the skies, said Mr Hwa.

He also noted that the tool will improve the safety and efficiency of air traffic control operations, while easing the cognitive task of processing information for air traffic controllers.

It is expected to improve the capacity of Changi Airport’s runways and help air traffic controllers do their work better, after a 2020 study showed that controllers in Singapore may apply slightly longer time gaps than the minimum safety duration required, and that safety durations set for various aircraft differ across controllers.

Speaking on the sidelines of the Singapore Airshow 2026 earlier in February, Ms Angela Ng, director of aviation industry at CAAS, said air traffic controllers around the world currently rely primarily on human cognition to get the safety distance between two aircraft right.

At present, in some airports worldwide, controllers evaluate distances between aircraft as shown on radar screens and base their calculations on the size, wingspan and weight of the aircraft.

Mr Hwa noted that there are 49 different permutations for the minimum distance between two aircraft, based on the type of aircraft. The time required to maintain this minimum distance ranges from 60 to 180 seconds.

For example, the minimum time gap for a wide-body Boeing B777 jet in front and a narrow-body Airbus A320 plane following behind is 100 seconds. On the other hand, the minimum duration for a larger wide-body Airbus A380 plane in front and a narrow-body Boeing B737-300 jet following behind is 160 seconds.

After taking in lessons learnt from the prototype, CAAS will incorporate the tool, with additional artificial intelligence capabilities, into the new air navigation system that is currently in development, said Mr Hwa.

Also earlier in February, Mr Simon Hocquard, director-general of the Civil Air Navigation Services Organisation, told reporters at the Changi Aviation Summit that automation of air navigation services is key to managing the surge in air traffic at airports.

He added that at present, air navigation operates in a “very tactical environment” where controllers have to talk to pilots to tell them what to do and where to go on a “reactionary” basis.

But if this process becomes more strategic and is accurately planned ahead of time through automation and technology, the capacity of the system can be further improved.

To achieve this, Mr Hocquard said every country would need to be coordinated in their investments in technology to enable the growth of the aviation ecosystem.

Editor’s note: This story has been amended following a clarification from CAAS that the tool does not have AI capabilities now. These capabilities will be introduced as part of the next-generation air navigation system.

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