The Air India conducted mandatory screening of at least 400 pilots to check for the use of banned substances, sources told NDTV Profit.
At least two pilots returned non-confirmatory results, with their samples now set to undergo detailed analysis.
However, a non-negative screening result does not necessarily mean that a banned substance was consumed.
The development comes after the August 4 Phuket-Delhi flight incident that triggered a wider review of drug testing procedures among Air India pilots.
The two pilots have been temporarily de-rostered, meaning they have been removed from flight duties while their cases undergo further testing. Their confirmatory or final test results are still awaited, NDTV reported.
ALSO READ: Air India Mandates Testing Pilots For Banned Substances After Phuket Flight Row: Sources
The airline had ordered all its pilots to get the drug test done, as part of new standard operating procedure (SOP), after the pilot-in-command of the Phuket-Delhi flight failed two urine tests he was asked to undergo when the flight landed.
The results of the final drug test usually take 24-48 hours to come, sources said.
NDTV also reported that a cabin crew member on the Phuket-Delhi flight was believed to have submitted a complaint alleging that the pilot had previously smoked "pot."
The flight that triggered these actions by the airline authorities involved an Airbus A-320Neo. The aircraft had dropped 300 feet, indicating there was a total and simultaneous loss of key control surfaces, including the elevators and ailerons, for four seconds.
The spoilers also lost control as a consequence of the same hydraulic failure. The incident left 24 passengers and crew members injured.
The elevators control the aircraft's pitch, while ailerons control its roll. Spoilers can reduce lift and increase drag. The temporary loss of these controls therefore represented a serious technical event.
The Aircraft Accident Investigation Bureau (AAIB) is investigating the incident, with Airbus and France's Bureau of Enquiry and Analysis for Civil Aviation Safety also involved.
The two pilots who have now failed preliminary screening have not been publicly identified in the reports, and the substances allegedly detected in their preliminary tests have also not been disclosed. Their temporary removal will remain in place pending the confirmatory testing process, NDTV reported.
ALSO READ: Air India CEO Meets Aviation Ministry Over Phuket Flight Incident
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