Air India Phuket-Delhi Flight Suffered Triple Hydraulic Failure, Pilot Tests Non-Negative For Drugs: AAIB

The preliminary investigation, conducted by the Aircraft Accident Investigation Bureau (AAIB), has found that there was a loss of pressure in all three hydraulic systems of an Air India Airbus A320 flying from Phuket to Delhi on 4 August, which caused the autopilot to disconnect, alert the crew to a stall warning and a severe altitude deviation.

The plane was flying at FL 360 at the time of the incident with 137 passengers on board at AI2379.

The preliminary report also contains a significant finding concerning the flight crew. Both pilots underwent psychoactive-substance detection tests, with the pilot-in-command testing non-negative for a psychoactive substance. The investigation into the incident remains ongoing.

All Three Hydraulic Systems Lost Pressure

According to the AAIB report, the aircraft’s flight-control system first detected a drop in pressure in the green hydraulic system.

Within seconds, pressure loss was also recorded in the blue and yellow hydraulic systems, resulting in a temporary loss of normal hydraulic support for the aircraft’s flight controls.

The autopilot subsequently disengaged, accompanied by a continuous repetitive chime. A stall warning was also triggered for approximately two seconds.

The hydraulic systems later recovered, allowing the aircraft’s flight-control surfaces to return to normal operation.

Aircraft Climbed Before Dropping Nearly 300 Feet

The hydraulic failure resulted in a substantial altitude upset.

While assigned to maintain FL360, the aircraft initially climbed by approximately 372 feet before descending around 292 feet from its assigned altitude.

The sudden movement caused passengers and cabin crew members to be thrown around the cabin. The seat-belt signs were reportedly off at the time of the incident.

The co-pilot, who was the pilot flying when the problem occurred, initially responded to the situation before the pilot-in-command took control.

24 People Injured

The incident resulted in injuries among people inside the aircraft.

After the aircraft landed in Delhi, 20 passengers and four cabin crew members received medical treatment.

Twenty of those injured were later discharged after being treated for minor injuries, while four people with more serious injuries required hospitalisation.

The aircraft itself also sustained damage inside the cabin.

Several Cabin Components Damaged

The altitude upset damaged multiple components within the passenger cabin.

The damage included overhead ceiling panels, passenger-service units and overhead-bin doors. An emergency-exit handle and handrails were also broken.

A fixture inside a lavatory was reportedly uprooted, while sections of crew seating were damaged during the incident.

Pilot Tests Non-Negative For Psychoactive Substance

The preliminary investigation has also raised concerns about the pilot-in-command’s psychoactive-substance test.

Both members of the flight crew underwent testing, with the captain returning a non-negative result for a psychoactive substance.

The finding is part of the ongoing investigation and does not by itself represent the final conclusion on the circumstances of the incident.

The AAIB will continue its investigation into the technical cause, crew actions and other aspects of the flight. A concluding investigation report should give a detailed account of the incident, and may include recommendations for additional regulatory or safety action.

ABOUT THE AUTHOR

Susmita Modak

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Always love to raise the unraised matter. In a world of worries, I am always ready to come over my comfort zone and taking the step ahead of spreading awareness.

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