Air India A320 Lost Elevators, Ailerons for Four Seconds in Mid-Air Incident

An Air India Airbus A320 flying from Phuket to Delhi experienced a sudden 300-foot loss of altitude on August 4 after all three hydraulic systems temporarily failed, according to an initial Airbus analysis.

Flight AI2379, carrying 145 people, suffered three hydraulic system failures within about two seconds, the analysis showed. The systems were subsequently restored within seven seconds. During the disruption, the aircraft’s elevators and ailerons were unavailable for around four seconds. Ailerons are movable surfaces on the wings that help control the aircraft’s left-right rolling movement, while elevators control its nose-up and nose-down movement.

Elevators control the aircraft’s pitch, or nose-up and nose-down movement, while ailerons control its roll. The Airbus analysis indicated that the loss of hydraulic pressure caused pressure switches to register a low-hydraulic condition, resulting in the loss of actuators.

The report said that just before 9:32:44 am IST, one hydraulic system was lost, followed by the failure of the other two at 9:32:45 am. All three systems were recovered by 9:32:51 am. During the brief period when the controls were unavailable, the first officer reportedly attempted a full nose-down input, but the flight controls did not respond. The aircraft later stabilised and landed safely in Delhi. At least 24 passengers were injured during the incident.

The Aircraft Accident Investigation Bureau (AAIB) is conducting a detailed investigation into the incident. The agency said it is examining the aircraft and its systems, recorded flight data, maintenance and operational records, medical information and human factors before reaching any conclusions.

Meanwhile, the investigation has gained an additional dimension after the pilot-in-command reportedly tested positive for a psychoactive substance. Air India has decided to conduct testing of more than 5,000 pilots across Air India and Air India Express.

The Airbus analysis, dated August 4, sought further information from Air India as multiple faults were recorded after the flight. The final cause of the altitude loss and hydraulic failures remains under investigation.