NEW DELHI: A major technical fault on the Air India plane flying from Delhi to Phuket on August 4 was responsible for the incident that injured 17 people on board, it is reliably learnt. Quick action by the two pilots may have saved the 145 lives on board AI 2379, it has now emerged.
While weather conditions were initially blamed for the incident, the revelation suggests that a technical problem with the aircraft had endangered the lives of the 137 passengers and eight crew members on board. Air India's change in its official account of the incident between its afternoon and late-evening statements, with the word 'turbulence' dropped from the latter, also points to this.
Speaking to TNIE, Captain Sam Thomas, the president of the Airline Pilot Association of India, said, "The A320 plane was entering Jharsuguda in Odisha around 10.30 pm when the Pilot-in-Command realised the aircraft had a triple hydraulic systems failure. These systems take care of flight controls and general functioning of the plane. As soon as the Flight Captain realised it had been a complete hydraulic failure, he immediately asked the co-pilot to take the nose down. This took the aircraft down by 300 metres. The dip in altitude creates a negative G and that only caused the passengers to be thrown around inside the aircraft. This quick action by the cockpit crew is responsible for saving countless lives on board."
Explaining the technical aspects, Thomas, who is in touch with pilots on a daily basis, said, "An Airbus A320 has three hydraulic reservoirs located in the belly of the aircraft and they are termed Yellow, Green and Blue. Pipes and steel tubes running from them connect them with the systems in the control surfaces of the plane."
Failure of all three systems is a rare occurrence, he said.
“In such situations, the cockpit crew sometimes take the plane down by even upto 800 feet to stabilise it. It is remarkable that they stabilised the plane by bringing down the altitude just by 300 feet,” he explained.
One of the pilots in the cockpit also found himself floating, he added.
Asked whether the pilot could have asked passengers to put on their seat belts before doing so, Thomas said, "He had to take decisions in split seconds. The protocol is always 'Aviate, navigate and communicate'."
The pilot had a choice of landing in Lucknow or New Delhi. He opted to land in Delhi as he felt it would have better medical facilities and he could reach in ten minutes time.
"The pilot managed to reach Delhi within seven minutes," Thomas said.
The data from the Cockpit Voice Recorder, when decoded, will clarify the exact parameters of the aircraft, he added.
Flip-flop by Air India
Notably, Air India in an official statement in the afternoon of the incident attributed it to "brief in-flight turbulence resulting in momentary change in altitude."
However, the official statement released by evening changed the version to "sudden loss of altitude during cruise", dropping the word 'turbulence'.
When pressed about the change in language, Air India sources asked TNIE to stick to the updated version.
The aviation regulator, the Directorate General of Civil Aviation, in its statement earlier in the day said "suspected transient technical fault" caused the sudden loss of altitude by approximately 300 feet.