India's civil aviation regulator, the Directorate General of Civil Aviation (DGCA) has commenced investigation into an alleged incident of "mid-air near miss" involving two IndiGo flights.
The purported safety-related lapse occurred on January 7 after the two flights took off from Bengaluru airport.
"Post the alleged safety breach, an investigation was launched by the DGCA," said a senior official with the regulator on Wednesday.
The two IndiGo flights were headed for Kolkata and Bhubaneswar, respectively.
According to industry insiders, the two aircraft had allegedly breached separation limits. Under safety regulations, aircrafts in Indian air space must maintain a distance of 5 nautical miles between them.
In its preliminary report, the DGCA noted that on January 7, two IndiGo flights 6E 455 (Bengaluru to Kolkata) and 6E 246 (Bengaluru to Bhubaneswar) were involved in breach of separation at Bangaluru airport.
In Bangaluru, there are two runways, namely North and South, with the first used for departures and the second for arrivals.
On the morning of the incident, both runways were in use.
"Later shift Incharge (WSO) decided for single runway operations i.e. North runway for arrival and departure. The south runway was closed but it was not communicated to the South Tower controller. South Tower controller gave departure to '6E 455' and at the same time North Tower controller gave departure to '6E 246' without coordination," the report said.
"As both aircraft, after departure, were on converging heading or moving towards each other, the approach radar controller gave diverging heading and avoided mid-air collision."
In addition, the report said that incident was "not recorded in any of logbook and also AAI has not reported this incident".