AI-2379, carrying 137 passengers and eight crew members, experienced a sudden loss of altitude of 300 feet.
An internal Air India Flight Safety report, accessed by NDTV, gives details of the chaotic few seconds on board when the co-pilot at the controls of the Airbus A320 was forced to push the aircraft into a sharp nose-down attitude to quickly gain airspeed and prevent the jet from stalling.
AI-2379, carrying 137 passengers and eight crew members, was on its way to Delhi from Phuket on August 4 when it experienced a sudden loss of altitude of 300 feet during its cruise phase. At least 20 passengers and four crew members were injured.
The ‘Flight Safety Department: Inflight Upset Stall Warning Event’ states that the captain of the flight was standing behind the first officer’s seat discussing the aircraft’s air conditioning system when aural and ECAM (Electronic Centralised Aircraft Monitor) alerts erupted together, warning that the aircraft was stalling. The autopilot disengaged and the nose pitched up. The first officer, who was flying at the time, responded with a trained stall-recovery response – pushing the nose down.
That manoeuvre produced a sharp negative-g excursion – the plane pitched down so sharply that, for a moment, it accelerated downward faster than gravity alone, making anything not strapped down, including the crew, float upward instead of being pressed into their seats.
The captain, still out of his seat at this stage, described watching the first officer and every loose object in the cockpit, including himself, float upward as the aircraft briefly went weightless. An amber caution on the Engine Warning Display later confirmed the jet had exceeded its -1g structural limit during the event.
The captain’s own account describes trying to steady the first officer mid-air while being thrown around the cockpit himself, then working his way diagonally back to his seat, activating the seatbelt sign as he did so. Once strapped in, he called out “I have controls” and took over. With the aircraft still descending, the pilot pushed the throttle to maximum continuous thrust to arrest the loss of speed and altitude. The aircraft lost a maximum of 300 feet before recovering.
Cascading Cautions After Recovery
Once the aircraft was stabilised, both pilots checked on each other and assessed the cockpit situation. Kolkata Air Traffic Control was notified, though the pilots eventually opted to land the A320 in New Delhi.
The report indicates that a “door arm forward emergency” caution appeared on the ECAM and reappeared twice more. Following manufacturer guidance, the crew ran the associated checklists, cross-checked system pressure pages, found all parameters normal, and judged the caution signs as being potentially spurious. A separate ‘transient hydraulic caution’ was cleared via the aircraft’s reset procedure. The crew said all actions followed standard operating procedures and normal cockpit task-sharing.
Engineering logs recorded a more serious underlying picture. Within the same minute, the aircraft registered low pressure in the Green hydraulic system, then in the Blue and Yellow systems together, and finally in all three, though not necessarily together. Hydraulic systems use pressurised fluid to power and move an aircraft’s flight controls, landing gear, brakes, and other heavy mechanical parts.
Alongside this, the aircraft’s autopilot disengaged and a left/right elevator fault was indicated. This suggests the aircraft’s pitch control may have been genuinely compromised, which is why investigators are examining whether this caused the sudden pitch-up. Pitch control refers to the pilot’s ability to raise or lower the aircraft’s nose, which determines whether it climbs, descends, or flies level.
Investigators have since confirmed this amounted to a triple hydraulic system indication – a serious and possibly unprecedented combination, since the A320’s three independent hydraulic systems are designed to back each other up. Maintenance teams carried out follow-up engineering checks and repairs after the aircraft reached Delhi.
Injuries In Cabin
The captain personally left the cockpit to inspect the cabin after coordinating with the cabin crew. He was told that several passengers and two cabin crew members had sustained serious injuries, and that cabin equipment had been damaged. Air Traffic Control was asked to arrange an ambulance lift, medical staff and orthopaedic specialists, and to allocate the parking bay closest to the runway exit for a faster medical response.
The aircraft landed safely in Delhi, though the bay it was ultimately assigned was farther from the runway than requested.
The Directorate General of Civil Aviation (DGCA) has classified the event as a serious incident, and the Aircraft Accident Investigation Bureau (AAIB) is investigating under the International Civil Aviation Organisation’s Annex 13 framework, with technical assistance from Airbus and France’s BEA.
High-flyer?
Under standard procedure following any serious occurrence, both pilots underwent a mandatory post-flight psychoactive substance screening. While the first officer’s result was clear, sources said on Tuesday that the captain failed both tests. Specifically, the second test reportedly confirmed that he had smoked marijuana.
Both pilots have been off-rostered.
Probe
In a statement, the Ministry of Civil Aviation said the Aircraft Accident Investigation Bureau (AAIB) has begun investigating the incident.
“AAIB is presently engaged in the systematic collection, preservation and examination of all relevant technical, operational, medical and human-factor evidences. This includes examination of the aircraft and its systems, recorded flight data, relevant operational and maintenance records, medical information, and interviews with persons concerned. All material evidence will be examined in its entirety before any conclusions are drawn,” the ministry said.
