Air India Phuket-Delhi Flight Pilot Tests Non-Negative For Psycho-Active Substance, AAIB Finds

The Aircraft Accident Investigation Bureau released its preliminary report on Friday into the Air India flight that experienced a mid-air scare on August 4, stating that the pilot-in-command was found "non-negative" for psycho-active substance use in a confirmatory test.

The report also disclosed that the aircraft's flight control system had briefly lost all three hydraulic systems while cruising over Odisha.

"The confirmation of use of psycho-active substance is a serious concern and AAIB recommends appropriate actions by DGCA on priority," the report said, calling for detailed investigation into the technical and other aspects of the incident.

What Happened Onboard

The flight, operating from Phuket to Delhi, encountered a sudden altitude drop of around 300 feet over Odisha, injuring 20 passengers and four cabin crew members. There were 145 people onboard, including 137 passengers, three infants, six cabin crew and two flight crew members.

The incident was initially described as turbulence, with the aircraft landing safely in Delhi. An AAIB team was sent to assess the situation, and based on the injuries recorded and evidence gathered, the occurrence was later reclassified as an accident.

Since the flight originated outside India, both flight crew members underwent a post-flight Breath Analyser examination on arrival in Delhi, which came back satisfactory, according to the report. They were then subjected to a psycho-active substance detection test using a detection kit, in which the pilot-in-command's sample was found non-negative.

Blood samples of both crew members were subsequently sent to a pathological laboratory for confirmatory testing. The pilot-in-command's confirmatory result was also non-negative, while the co-pilot's sample was negative in both rounds of testing. The pilot reportedly tested positive for psycho-active substances during post-flight screening, with a second test later also returning positive. Reports suggested the tests pointed to marijuana use, though the AAIB report itself does not specify the substance involved.

Citing the non-negative result for one of the flight crew members, AAIB recommended that the DGCA take appropriate action to prevent misuse of psycho-active substances among flight personnel.

Hydraulic Systems Failed Briefly Mid-Flight

The Airbus A320 aircraft is equipped with three hydraulic systems, identified as green, blue and yellow, which together supply hydraulic power at 3,000 psi to the aircraft's main systems. According to the report, the aircraft first registered a loss of the green hydraulic system, followed shortly after by the loss of the blue and yellow systems.

The co-pilot, who was flying the aircraft at the time, responded and attempted to control the situation before the pilot-in-command took over the controls. During this period, the aircraft experienced an altitude upset, climbing 372 feet before dropping 292 feet from its assigned flight level of 36,000 feet.

The blue hydraulic system was restored a short while later, followed by the recovery of the yellow and green systems within seconds of each other. This allowed the flight control surfaces to return to normal, and the aircraft's operation stabilised, the report said.

The report noted that the aircraft sustained damage inside the cabin, mainly to the overhead stowage bins and ceiling panels.

Maintenance personnel had carried out a pre-flight inspection before departure from Phuket International Airport, and no discrepancies were recorded apart from an already invoked Minimum Equipment List entry. The flight crew also conducted a walk-around inspection of the aircraft before departure and reported no issues at the time.

The AAIB said detailed investigation into both the technical failure and the substance test findings is currently underway.