Mumbai: A Jet Airways flight from Chennai
came dangerously close to an Air India aircraft over Mumbai
after it was asked to descend to 11,000 feet by the ATC but a
last minute alert averted a mid-air collision.
The Mumbai-bound Jet Airways Konnect flight 9W 2119, with
142 passengers on-board, was instructed by the Air Traffic
Control to descend to 11,000 feet on Saturday.
When the flight was on descent, the Traffic Collision
Avoidance System (TCAS), a hi-tech system designed to reduce
the incidence of mid-air collisions between flights, alerted
the aircraft about Air India flight IC 174 being in its way, a
The Air India flight had 70 passengers on-board and was
also on way to Mumbai from Chennai.
TCAS monitors the airspace around an aircraft for other
aircraft equipped with a corresponding active transponder,
independent of air-traffic control, and warns pilots of the
presence of other transponder-equipped aircraft
which may present a threat of mid-air collision (MAC).
As a rule, two aircraft are required to maintain a
vertical separation of 1,000 feet and lateral separation
If any aircraft breaches these limits, TCAS sends out an
When contacted, an Air India spokesperson said the report
filed by the pilot of its flight suggested that an aircraft
was noted to be on its way.
"Our commander of flight IC 174 on July 10 has made an
observation in his report regarding another aircraft while
approaching Mumbai," the spokesperson said.
Jet Airways also said its pilot had received an alert
message, advising of another aircraft in the vicinity.
"The flight 9W 2119 (Chennai-Mumbai) had a Resolution
Advisory (RA), an alert message advising of another aircraft
in the vicinity. This incident took place while holding over
Mumbai under ATC instructions," Jet Airways said.
The Directorate General of Civil Aviation (DGCA) is
investigating the matter.