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Recent cockpit recordings from the Air India flight that crashed a month ago indicate that the captain may have intentionally cut off fuel supply to the aircraft’s engines, according to sources familiar with the preliminary examination by US officials.
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Here are some key details regarding fuel switches, their roles in aviation, and specifics concerning the incident involving the Air India flight.
Understanding fuel switches
Fuel switches are devices that control the flow of fuel to an aircraft’s engines. Pilots use them to start or shut down engines during ground operations or to manually manage engine power in the event of a malfunction during flight.
Aviation analysts assert that it is nearly impossible for a pilot to accidentally engage the fuel switches. If these switches are manipulated, the change in engine power would be instantaneous, leading to a loss of thrust.
According to aviation safety expert John Cox, the systems and wiring that govern the fuel cutoff switches and corresponding valves operate independently.
Location of fuel switches
In a Boeing 787, like the one operated by Air India with two GE engines, the fuel control switches are positioned beneath the thrust levers.
These switches are designed to stay in place until manually adjusted. To shift the switch from ‘RUN’ to ‘CUTOFF’, a pilot must first lift the switch before changing its setting.
There are two operational modes: ‘CUTOFF’ and ‘RUN’.
Details of the tragic incident on the Air India flight
Flight recorder data reveals that shortly after taking off, the fuel switches for both engines shifted from ‘RUN’ to ‘CUTOFF’ in succession, occurring one second apart. Consequently, the engines started to lose power.
One pilot was heard questioning the other about the fuel cutoff. The responding pilot denied making such an adjustment, as indicated in the report.
The identities of the captain and first officer’s comments were not revealed in the findings.
The first officer, who was operating the 787, inquired why the captain had changed the fuel switches, resulting in fuel deprivation to the engines, and urged him to restore the fuel flow, as stated by the informed source on the US officials’ initial evaluation.
Both switches were eventually returned to ‘RUN’ and were found in that position at the crash site, according to the preliminary investigation.
When fuel switches are shifted from ‘CUTOFF’ to ‘RUN’ during flight, the engines’ control systems automatically initiate a sequence to reignite and recover thrust by restoring fuel flow, as per the report.
US aviation safety analyst John Nance commented, “No rational pilot would turn those switches off mid-flight,” particularly during the aircraft’s initial ascent.