New Delhi, Sept. 4 -- The Aircraft Accident Investigation Bureau (AAIB) has found that the pilot-in-command of an Air India flight from Phuket to Delhi tested positive for a psychoactive substance in a confirmatory test and has recommended that the Directorate General of Civil Aviation (DGCA) take "appropriate action" on priority.

The preliminary report does not link the pilot's psychoactive-substance test result to the altitude upset or establish the cause of the hydraulic-system disruption yet.

The 4 August incident involved Air India flight AI2379, an Airbus A320-251N carrying 145 people. The flight lost pressure in all three hydraulic systems while cruising at 36,000 feet, gained 372 feet and then fell 292 feet, injuring 24 people, ...