CHENNAI: People flying over the Indian Ocean can heave a sigh of relief as their aircraft can now be tracked by Air Traffic Controllers (ATC) in Chennai after the Ministry of Civil Aviation introduced a space-based technology, which is on a trial basis and will be introduced soon at Chennai Air Traffic Control.
The technology, known as space-based Automatic Dependent Surveillance-Broadcast (ADS-B), an air traffic surveillance technology that relies on aircraft broadcasting their identity, a precise GPS position, and other information derived from on-board systems through satellite has come in handy for Air Traffic Controllers. Rolled out on a trial basis for the last one year, the technology is likely to be introduced soon, said an ATC official.
The air space over the Indian Ocean of 800 nautical miles to 1,000 nautical miles is called the grey area. International aircraft flying in this stretch could not be detected for an hour. Now, this is being resolved as flights can now be tracked with the space-based Automatic Dependent Surveillance Broadcast.
Flights could not be tracked as the land-based ADS-B could not be installed since the entire air stretch is an ocean. “Now, we are using satellite technology. Space-based ADS-B bypasses the limitations of ground-based systems and provides an operational, global, space-based air traffic surveillance solution to all aviation stakeholders,” said ATC sources, who are marking the International Day of Air Traffic Controllers 2022.
Usually, more than 1,000 aircraft pass through this oceanic space and the weather on this stretch is choppy at times, causing worry among air traffic controllers who are unaware of the flight path. “The success of this technology during the trial could result in phasing out the land-based ADS-B or radar,” said an ATC official. All commercial aircraft have been mandated to use ADS-B technology so they can be tracked, he added.
To a query on the crash of AN-32, which went down in the grey area and could not be tracked, an ATC official said defence aircraft don’t use the technology and the aircraft did not possess Controller Pilot Data Link Communications, a means of communication between the controller and pilot, using a data link for ATC communications.
Currently, after the airspace was opened up post Covid, there have not been many aircraft in this stretch. “It is slowly improving but is not what it used to be. There would be around 600 aircraft movements on an average,” he said.
Similarly, there is a move to migrate air traffic communications to an Internet Protocol (IP)-based system, referred to generally as the Internet Protocol Suite (IPS). “This is more like a normal voice transmission, where the pilot would be in direct touch with the ATC through the internet and not through radio waves. In most parts of the country, there have been shadow areas where domestic flights could not be detected till the flight reaches 20,000 feet,” said an official.