Air India A320 briefly lost key flight controls during 300-foot drop, Airbus analysis shows

An Air India Airbus that dropped about 300 feet this month, injuring 24 people on board, briefly lost key flight controls after registering losses in all three hydraulic systems, according to a preliminary Airbus analysis reviewed by Reuters.

The August 4 incident occurred on Air India flight AI2379 from Phuket to Delhi, which landed safely in Delhi despite the altitude loss.

The aircraft's elevators and ailerons, which control its pitch and roll, were unavailable for about four seconds, during which the plane pitched upward, Airbus said in a communication responding to an Air India request for an assessment.

During that period, the first officer applied a full nose-down input, but there was "no direct response" from the flight-control surfaces before the hydraulic systems recovered within seconds.

In the analysis, Airbus asked Air India to conduct checks on the plane's systems and sensors and to provide more information about the incident. It did not establish the root cause.

Air India and Airbus did not immediately respond to requests for comment.

Indian authorities have classified it as a serious incident, and the Aircraft Accident Investigation Bureau is investigating, with technical assistance from Airbus and France's BEA.

The flight's captain tested positive for a drug test, according to a source familiar with the matter. No link between the test result and the altitude loss has been established to date, but Air India on Thursday began mandatory substance testing for all pilots, according to an internal memo.