The Aircraft Accident Investigation Bureau (AAIB) has released its preliminary report on the serious mid-air incident involving an Air India flight from Phuket to Delhi last month. The findings highlight sudden hydraulic system failures that caused severe turbulence, injuring passengers and crew. According to the report, the Airbus A320 aircraft experienced a rapid loss of pressure in all three hydraulic systems within seconds, leading to the disconnection of autopilot and activation of stall warnings. The aircraft abruptly shifted 664 feet above and below its assigned altitude, triggering chaos inside the cabin. The incident occurred on August 4, with 145 people onboard, including 137 passengers and 8 crew members. A total of 24 individuals were injured, comprising 20 passengers and 4 cabin crew. Four of them sustained serious injuries and required hospitalization. The turbulence was so intense that cabin ceiling panels broke, overhead bins detached, and even a lavatory fixture was displaced. Pilot’s Drug Test Raises Concerns The AAIB report also revealed that the 34-year-old pilot-in-command tested “non-negative” for a psychoactive substance in both initial and follow-up blood tests, while the co-pilot’s results were negative. The bureau has urged the Directorate General of Civil Aviation (DGCA) to take immediate steps to prevent such substance use among flight crew. Maintenance Under Scrutiny Investigators found that the aircraft (VT-EXO) had been operating since July 28 despite a known defect in its Power Transfer Unit (PTU). While this fault has not yet been directly linked to the incident, hydraulic components have been seized for further technical examination. Airbus experts from France have also inspected the aircraft in Delhi. Timeline of Events The AAIB report details the sequence: 04:02:43 UTC – Green hydraulic system pressure dropped. 04:02:47 UTC – Blue and Yellow systems failed. 04:02:48 UTC – Autopilot disconnected, continuous warning alarms sounded. The aircraft climbed 372 feet above its assigned altitude before dropping 292 feet below. Systems later recovered automatically, and the pilots chose to continue to Delhi rather than divert, landing safely. The bureau emphasized that this was a technical incident, not weather-related, as no adverse conditions were reported by pilots or air traffic control. The investigation into the root causes remains ongoing.