The pilot of an Air India flight that suddenly lost 300 feet in altitude during a Phuket-Delhi journey has tested “non-negative” for a psycho-active substance, according to a preliminary investigation report.
The development has emerged in the probe into the August 4 incident involving flight AI2379, in which 20 passengers and four crew members were injured after the aircraft experienced a sudden loss of altitude during cruise.
AAIB flags pilot test result
The preliminary report said the pilot's test indicated the presence of a psycho-active substance. Earlier reports had said the pilot's preliminary drug test was “non-negative” for marijuana.
The Aircraft Accident Investigation Bureau (AAIB) has called the finding a serious concern and recommended action by the aviation regulator.
“The confirmation of use of psycho-active substance is a serious concern and AAIB recommends appropriate actions by DGCA on priority,” the latest report said.
The investigation is continuing, and the final report will be issued after the detailed probe is completed.
Hydraulic issue linked to altitude loss
Air India had initially attributed the incident to turbulence. However, a report from the French aircraft manufacturer indicated that the aircraft's loss of altitude was linked to low hydraulic pressure in its Green, Blue and Yellow systems.
The hydraulic issue resulted in a temporary loss of control of the elevator and aileron surfaces for about four seconds.
Post-flight data also showed several warnings during the flight. At 9.32 am IST, at least nine warning messages were recorded within a minute, including alerts related to low hydraulic pressure, an autopilot disconnect and an elevator flight-control fault.
Two emergency-exit door sensor warnings followed at 9.33 am and 9.35 am. An engine anti-ice fault was recorded at 10.16 am, while another autopilot disconnect appeared at 10.52 am.
Investigators examine pilot conduct
Sources close to the investigation also told Hindustan Times that the pilot slept for at least 30 to 35 minutes during the flight.
The findings are part of the ongoing investigation into the incident. Authorities are examining the aircraft's technical data as well as other circumstances surrounding the sudden altitude loss and the injuries sustained during the flight.