Saudia, Gulf Air jets avert midair collision 

(MENAFN - Arab News) Alert Air Traffic Controllers (ATC) at the Mumbai airport averted a major mid-air collision between two aircraft that came within a vertical separation height of 800 feet, 200 feet less than what it should have been.

An ATC official told Arab News that the incident occurred on Thursday night about 120 nautical miles west of Mumbai, and was noticed when the Traffic Collision Avoidance System (TCAS) of the Gulf Air flight GF 064 heading toward Mumbai alerted the pilot of an intruding aircraft — Saudi Arabian Airlines SV 601.

The Gulf Air flight, which had taken off from Bahrain, was descending to land in Mumbai with 180 passengers on board. The Saudia flight, a Boeing 747, was flying over the Mumbai airspace on way to Jeddah from Dhaka and had 377 passengers on board. The Saudia aircraft, the ATC official said, had deviated from its flight path and had climbed 200 feet without permission from the ATC. The pilot of the Gulf Air aircraft spotted the Saudi aircraft climbing into its airspace on his warning system.

The ATC intervened at this stage and asked the Saudia pilot to maintain its given altitude. The ATC official said that the Saudia aircraft was cruising at an altitude of 35,000 feet, when the resolution advisory (RA) system on board the aircraft went off and alerted the Saudia pilot that an aircraft (Gulf Air) was 800 feet near it vertically.

The vertical separation minima between two aircraft are 1,000 feet. The Saudia pilot informed the ATC that probably due to passenger movement in the aircraft, the center of gravity on the plane was disturbed and he had to climb 200 feet, reducing the vertical minima between him and the Gulf Air aircraft, and at that time, the Saudia aircraft was at 34,000 feet. The digital radar at the ATC also spotted the Saudi aircraft moving up in height.

"Earlier we could not have spotted the aircraft exceeding its altitude as the radars were analogue, but now with the digital radars the exact height of the aircraft can be traced," the ATC official said.

As the RA went off, the computer guided the Gulf Air pilot to climb 200 feet above, bringing back the separation between the two aircraft to 1,000 feet.

By Shahid Raza Burney