New Delhi, Aug. 13 -- Air India has initiated mandatory screening of all group pilots for unauthorised substances and medications starting Thursday, as regulatory scrutiny intensifies over the airline, according to sources.

The Aircraft Accident Investigation Bureau (AAIB) is likely to submit its preliminary report on the Phuket-Delhi incident to the International Civil Aviation Organisation (ICAO) before the second week of September, top sources told ANI.

Meanwhile, the government is expected to expedite the preliminary report into the August 4 Phuket-Delhi Air India flight incident.

The move comes after Air India flight AI2379, operating from Phuket to Delhi on August 4, experienced a sudden 300-foot altitude drop over Odisha, leavin...