Air India Crash Points to Cockpit Confusion as Fuel Flow Cut Out

Mint

15 hours ago

(Bloomberg) -- The Air India jetliner that crashed on June 12 was doomed almost immediately upon taking off, after both engines lost fuel supply and the pilots ran out of time to regain control and avert catastrophe.
A preliminary 15-page report filed on July 11 provided the first detailed account of the fateful 32 seconds between takeoff in Ahmedabad and the descent into an urban district just beyond the airport perimeter, where the Boeing Co. 787 exploded, killing all but one of the 242 people on board.
Investigators laid out the sequence of events with exact timestamps, providing a harrowing picture of the plane's final moments. But the findings leave unanswered one central question: Why and by whom were two fuel switches in the cockpit moved to a cut-off position as the jet nosed into the air, starving the two powerful engines of thrust just as the plane required the most lift.
At the controls for the aircraft's final journey was First Officer Clive Kunder, a pilot with roughly 1,100 flight hours on Boeing's most advanced jet. The report identified him as pilot flying, while Sumeet Sabharwal, the more experienced and senior cockpit occupant in command, was pilot monitoring for the flight.
It's common for a captain and co-pilot to switch flying duties, particularly on longer journeys. Under typical pilot protocol, Kunder would have had one hand on the yoke commanding the widebody into the skies, and another on the throttle controlling the plane's speed. The crew captain would have handled air traffic communications and responded to Kunder's instructions.
All seemed normal as the Boeing 787 lifted off into a clear sky in the western Indian city en route to London's Gatwick airport. There was no significant bird activity in the flight path, all but ruling out a collision that could have damaged the engines.
Then, according to a chronology laid out by Indian authorities, the two fuel switches in the plane's center console were flipped, about one second apart.
It's unclear what prompted the maneuver, but it crippled the plane during a critical phase of flight. A fan, known as the ram air turbine, dropped below the plane's belly to provide emergency power, all while the 787 was still within view of airport cameras.
On board, the pilots had a brief exchange — the only cockpit conversation mentioned in the report aside from a final 'mayday' call just seconds before impact.
'In the cockpit voice recording, one of the pilots is heard asking the other why did he cutoff,' the investigators wrote. 'The other pilot responded that he did not do so.' The report didn't identify which of the two men asked the other about the move.
It would take about 10 seconds for the first switch to return to its run position, restoring the flow of fuel to the engine, and 14 seconds for the second to be turned back on. Given the aircraft had barely lifted off and was at a critical phase of its flight, that's an eternity for pilots only a few hundred feet above ground and facing a life-threatening emergency.
'It's just strange,' said Bjorn Fehrm, an aerospace engineer and former fighter pilot who is a technical analyst with Leeham News. 'I would never, ever wait 10 seconds to put them on again. I would put them on in a jiffy.'
While both engines were relit, only the first one started to regain power before the 787 plunged to the ground.
The sequence of events was gleaned from different data points, including the cockpit voice and flight-data recorders that were recovered from the wreckage. There's no mention in the report of any additional exchanges in the cockpit or of any noises on the flight deck that the sensitive microphones would have picked up.
'The most important information is the voice dialog between the pilots, and we only get one line, which is totally inadequate,' said Fehrm.
That leaves other key questions unanswered, including how the two pilots interacted as the aircraft sagged back to the ground, and who was ultimately in control in those frantic final seconds. Why one of the men would have conducted the unusual and highly risky maneuver of manipulating both fuel toggles also remains unknown.
The switches are secured with a mechanism that requires a specific movement to shift them between on and off mode. And they are idled only when the plane is on the ground, or in an extreme emergency during flight, such as an engine fire.
Given the trajectory of flight, starving the aircraft of fuel seconds after takeoff made it almost impossible to save the plane because the jet had just left the ground, providing very little recovery room. The Boeing 787 crashed just outside the airport boundary, having grazed some trees before plunging into a hostel packed with students.
Some 19 people died on the ground, the report found.
The preliminary version hinted at another matter to be explored by investigators, without elaborating. It flagged an airworthiness bulletin by the Federal Aviation Administration from 2018 that said that some fuel control switches on Boeing planes including the smaller 737 and the 787 were installed without their locking mechanism engaged.
The Air India jet was not inspected for that mechanism fault as the matter was not mandatory. No defect relating to the switches had been reported since the throttle control module was replaced in 2023, the report said.
Investigators said that they found no evidence so far that would require them to take actions over the Boeing aircraft or the GE Aerospace engines powering it.
'At this stage of investigation, there are no recommended actions to B787-8 and/or GE GEnx-1B engine operators and manufacturers,' according to the report from the Aircraft Accident Investigation Bureau.
The National Transportation Safety Board referred any questions to Indian authorities. Air India said it's unable to comment on specific details of the investigation and it was cooperating with officials. Boeing said it continues to support the investigation and Air India and referred questions to the AAIB.
The people conducting the probe are also looking at the backgrounds and experience of the pilots — a normal step for this kind of investigation. Sabharwal had about 8,500 flight hours, according to the report. Both pilots were based at Mumbai and had arrived in Ahmedabad the previous day with 'adequate rest period' prior to the flight, the report said.
'We now know — with some degree of confidence — that both engines rolled back because these fuel switches were activated,' said Jeff Guzzetti, a former accident investigation chief for the US Federal Aviation Administration. 'We just don't know why or how these switches were activated and that's going to be a big part of this investigation.'
A final report that seeks to determine the cause of the incident will take months to compile.
--With assistance from Anthony Palazzo and Mary Schlangenstein.
More stories like this are available on bloomberg.com