Air India Phuket flight incident: AAIB initial probe report out; pilot blood test confirms drug use

The pilot-in-command of an Air India flight that suffered a mid-air hydraulic system failure and altitude upset last month was found non-negative for a psychoactive substance in a confirmatory blood test, prompting the Aircraft Accident Investigation Bureau (AAIB) to recommend priority action by the aviation regulator.

The AAIB, in its preliminary report into the August 4 accident involving Air India's Phuket-Delhi flight AI-2379, said the pilot's initial psychoactive substance detection test was also non-negative.

A subsequent confirmatory blood test returned a non-negative result, while the co-pilot tested negative in both tests.

The report termed the confirmation of use of a psychoactive substance a "serious concern" and recommended that the Directorate General of Civil Aviation (DGCA) take appropriate action to prevent abuse of psychoactive substances.

"We acknowledge the release of the preliminary report by the Aircraft Accident Investigation Bureau (AAIB) and continue to extend our full cooperation to the investigation, including providing access to all relevant operational, maintenance and technical records," an Air India Spokesperson said in a statement.

"Our pilots undergo rigorous training, regular proficiency checks, medical examinations and other regulatory assessments in accordance with applicable national and international requirements. Following the incident, Air India has started voluntary testing of 100% of its pilots as a further step to reinforce its safety-first approach," the spokesperson added.

The development comes as the AAIB investigates the circumstances surrounding the accident involving the Airbus A320-251N aircraft, which was carrying 137 passengers and eight crew members.

What happened on August 4

The aircraft was cruising at flight level 360 over the Kolkata Flight Information Region when its flight-control system detected a loss of the green hydraulic system at 9:32:43 am IST on August 4.

Four seconds later, losses of the blue and yellow hydraulic systems were detected.

The autopilot disengaged and a stall warning was triggered.

The aircraft subsequently gained 372 feet and lost 292 feet from its assigned altitude before the hydraulic systems recovered and the flight-control surfaces returned to normal.

The seat-belt signs were off during the incident and some passengers and cabin crew were injured.

The flight continued to Delhi rather than diverting to the nearest airport and landed safely at IGI Airport at 11:00 am IST.

A total of 24 people were injured in the incident and they received medical assistance at Delhi airport.

Twenty were discharged after treatment for minor injuries, while four with serious injuries were hospitalised.

The AAIB said the investigation into the technical and other aspects of the accident is still underway.

Flight recorder data has been downloaded and is available with the investigation team, while hydraulic components and samples have been collected for further analysis.