The Air Traffic Controller inadvertently gave instructions to one aircraft to continue taxiing through a particular taxiway mixing its location with that of another plane that led to a near collision at Delhi airport on Tuesday, according to the Airports Authority of India.
In a major safety lapse, two aircraft of IndiGo and SpiceJet came face-to-face barely 40 metres away on the same taxiway on Tuesday but providentially a disaster was averted after commanders of both the planes alerted the air traffic control and switched off their engines.
Following the incident, the air traffic controller has been derostered pending investigation.
While acknowledging that an air traffic controller mixed the locations of the two flights, the AAI on Wednesday also said that SpiceJet flight did not question the incomplete ATC instruction for taxiing, adding that these human errors resulted in "traffic conflict situation".
In a detailed statement, AAI said IndiGo flight (6E-769) from Lucknow to Delhi after landing on runway-28 was taxiing via taxiway 'E2' for parking stand 12 as advised by ATC.
The departing flight of SpiceJet (SG123) was not able to take off from runway 28 due to poor visibility and waiting to return to apron for parking, it said.
Accordingly, the controller instructed SG123 to taxi via taxiway C and hold short of the taxiway 'E2' so that the two flights were not in conflict with each other.
"The traffic density being high and complex, the controller inadvertently gave instructions to SG123 to continue taxi via E to stand 130, mixing its location with the location of SG263 which was holding on another taxiway 'E' for departure.
"However, SG123 also did not question the incomplete ATC instruction for taxiing. These human errors resulted into traffic conflict situation. However, both aircraft stopped at safe distance and there was no risk to aircraft or passengers," AAI said.
Noting that the statement is being issued to avoid any fear among air passengers after Tuesday's incident, the AAI said at times it may not be possible to eliminate human error.
"At times it may not be possible to eliminate human error whether it is aviation or other industries but continuous efforts are being made by AAI to offset such human errors through Standard Operating Procedures, recurrent training to the controllers and introducing technology," it said.
Further, the AAI said various reports appearing in the media are giving exaggerated version stating that the passengers had close shave, indicating a distorted interpretation that may create fear in the minds of air passengers.
Safety record of ATC provided by AAI at Indian airports has been very good and comparable to best in the world, it added.