Air India flight AI2379 recorded multiple hydraulic, autopilot and flight-control warnings before a sudden 300-foot altitude loss on August 4.
A maintenance report from Air India flight AI2379, which operated from Phuket to Delhi on August 4, indicates that the aircraft recorded multiple technical warnings around the time it experienced a sudden 300-foot loss of altitude during cruise.
The incident injured several passengers and crew members. Air India initially described the event as turbulence-related before removing the reference to turbulence from its later statement.
The Airbus A320neo was carrying 137 passengers and eight crew members. The aircraft landed safely in Delhi at 11:07 am, according to Air India’s updated statement.
The maintenance report was printed in the cockpit at 11:14 am after the aircraft landed in Delhi.
At 1:14 pm, Air India said the aircraft had experienced a “brief in-flight turbulence-related event during cruise”, resulting in a momentary change in altitude. The airline initially said that a small number of passengers and crew members had minor injuries and were taken for medical assessment.
Five hours later, at 6:55 pm, Air India issued an updated statement. The reference to turbulence was removed, with the airline instead describing the incident as a “sudden loss of altitude during cruise”.
The revised statement said 13 passengers and four crew members sustained injuries and were taken to hospital for medical evaluation.
However, the statement did not mention the hydraulic warnings or other technical issues recorded in the maintenance report.
According to the report, warnings indicating low pressure appeared in all three hydraulic systems at around 9:32 am. Low fluid levels were also recorded in two hydraulic reservoirs.
The report also indicated that the autopilot disconnected at around the same time and that faults were flagged in the aircraft’s left and right elevator controls.
Further warnings followed. At 9:33 am, a warning was recorded for the right front emergency exit door, while another warning involving the right rear door appeared at 9:35 am.
At 10:16 am, the aircraft’s Engine 1 anti-ice system recorded a fault linked to a valve pressure issue. The autopilot disconnected again at 10:52 am.
A warning on an aircraft maintenance report does not necessarily mean that a system completely failed. However, the combination of hydraulic, flight-control and autopilot warnings is significant and would warrant investigation by aviation safety and maintenance authorities.
The incident is also being examined in connection with the pilots.