AIRCRAFT WITHIN 8KM OF EACH OTHER

AIRCRAFT WITHIN 8KM OF EACH OTHER

Near miss: Chennai-bound plane 300ft away from Vadodara flight

Mid-Air Incident On Jan 29 Over Mum Airspace

Manju.V@timesgroup.com

Mumbai:24.08.2021

The final investigation report into the January 29 near-miss involving an AirAsia India flight from Ahmedabad to Chennai and an IndiGo flight from Bengaluru to Vadodara over Mumbai airspace has found that the two aircraft came within 8km of each other with 300ft vertical separation between them.

The report also looked into the changes brought about due to the pandemic which had restricted manpower at the Mumbai air traffic control.

The serious incident occurred over an area about 30km east of Vapi. To fly from Ahmedabad to Chennai, aircraft typically overfly Bhavnagar, but on that day, the AirAsia flight plan had the aircraft follow a route that is normally taken by aircraft descending to land in Mumbai, said the report released recently by the Aircraft Accident Investigation Bureau. Also, the IndiGo aircraft coming in from the south was allowed to head directly to a point that lies over Ankleshwar, near Bharuch. Due to these changes in routing, both the aircraft were now flying towards each other, at different altitudes though. The automated system at the Mumbai air traffic control issued a ‘predicted conflict warning’, which the radar controller failed to respond to, the report said.

By the time the controller realised the potential conflict, the AirAsia aircraft at 38,008ft and the IndiGo aircraft at 38,000ft were closing in.

‘Potential mid-air collision also a result of changes brought on by pandemic’

The automated traffic collision avoidance system (TCAS) in the AirAsia cockpit blared an aural command instructing the pilots to climb. The aircraft climbed up to 38,396ft, moving safely away from the 38,000ft altitude that IndiGo was on. The report said that the minimum separation between both aircraft was recorded as 8km laterally when the climbing AirAsia aircraft was 300ft below IndiGo aircraft and it was 6.5km laterally when the AirAsia aircraft was 500ft above IndiGo aircraft after having crossed its path.

The report recommended suitable corrective training for the radar controller concerned. But the potential midair collision was also a result of the changes brought on by the pandemic. With limited manpower in the Mumbai air traffic control and fewer flights, the controller handled traffic over a much larger area. While air traffic was down after the two-month ban on domestic flights in summer 2020, it had picked up considerably in the latter half of the year, and by January, the workload on the lone controller would have gone up. The report recommended that the Airports Authority of India reassess the volume of traffic in all sectors which were withdrawn due to less number of traffic during the Covid-induced lockdown and implement sectors as before the pandemic.

The report also looked into the changes brought about due to the pandemic which had restricted manpower at the Mumbai ATC