India, Sept. 5 -- The Aircraft Accident Investigation Bureau (AAIB) on Friday released its preliminary report on the Air India Phuket-Delhi flight that dropped nearly 300 feet on August 4. While the report details the sequence of events, experts have flagged key questions that remain unanswered.

The Airbus A320neo had experienced a major "altitude upset" while flying at 36,000 feet, leaving at least 24 people injured.

According to the report, the aircraft lost all three hydraulic systems within seconds, triggering a stall warning and a subsequent drop in altitude. The systems recovered seconds later, allowing the flight to resume normal operations. However, former pilots say the AAIB report leaves the central technical question open.

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