A preliminary report by the Aircraft Accident Investigation Bureau (AAIB) says an Air India Airbus A320 operating from Phuket to Delhi experienced the near-simultaneous loss of all three hydraulic systems while cruising at 36,000 feet on August 4. The failure triggered an autopilot disconnect, a brief stall warning, and an altitude upset that injured 24 people. The aircraft was carrying 145 people.

The report also disclosed that the pilot-in-command tested positive for a psychoactive substance in a confirmatory test conducted after the flight. AAIB described the finding as a 'serious concern' and recommended that the Directorate General of Civil Aviation (DGCA) take appropriate action to prevent the abuse of psychoactive substances.

The report, however, does not establish that the pilot's drug use contributed to the hydraulic failure or the altitude upset.