Air India Flight’s Sudden 300-Foot Drop Triggers Pilot Testing, AAIB Probe

The pilot-in-command of an Air India flight that suffered a sudden altitude loss on a Phuket-Delhi flight has undergone confirmatory testing after an initial psychoactive substance screening produced a result requiring further analysis, the Civil Aviation Ministry said on Sunday.

The Airbus A320, operating Air India flight AI2379, was flying from Phuket to Delhi on August 4 when it unexpectedly lost around 300 feet of altitude during cruise. The aircraft subsequently stabilised and landed safely in the national capital.

A few passengers and cabin crew members reported injuries following the incident. The flight was carrying 137 passengers, including three infants, and eight crew members.

In line with standard operating procedures, both members of the flight crew underwent mandatory psychoactive substance screening after the incident.

According to the ministry, the pilot-in-command’s sample was sent to a designated laboratory for confirmatory analysis, with the final report still awaited. The ministry did not disclose the initial screening result.

The incident has been classified as a serious incident and is under investigation by the Aircraft Accident Investigation Bureau (AAIB), which is examining the circumstances.

Pending completion of the investigation and laboratory testing, the Directorate General of Civil Aviation (DGCA) has removed both flight crew members from the roster, the ministry said.

Further action will be considered after the investigation findings and confirmatory test results are available.

The episode comes as aviation authorities maintain strict safety protocols, including psychoactive substance screening for flight crews. Such testing is intended to establish whether a crew member may have been affected by substances that could impair operational fitness.

The ministry’s statement makes clear that the initial screening does not constitute a final finding. The pilot’s confirmatory laboratory report will therefore be an important part of the ongoing assessment.

Authorities have not indicated any conclusion about the cause of the altitude loss. The AAIB investigation and pending laboratory report are expected to provide further clarity and determine whether additional regulatory or operational measures are warranted.