Fuel switches explained: Cockpit levers at the centre of the Air India 171 crash investigation

A preliminary report into the deadly crash of Air India Flight AI171 reveals a critical failure just seconds after takeoff: both engine fuel control switches were moved to ‘CUTOFF’, starving the engines of fuel and triggering a rapid, fatal descent.

These switches—small but powerful—control the flow of fuel to a plane’s engines. Located below the thrust levers in the cockpit of the Boeing 787, they allow pilots to start or shut down engines during ground operations, or to manually stop and restart them midair in case of an emergency. The switches are spring-loaded and require a deliberate pull-up and shift motion to change modes—either to ‘RUN’ to allow fuel flow or ‘CUTOFF’ to stop it.

On the morning of June 12, the 787 Dreamliner lifted off from Ahmedabad en route to London. Within moments, the flight data recorder captured a stunning sequence: both fuel switches flipped from ‘RUN’ to ‘CUTOFF’ one after another—just one second apart. The engines immediately began losing power.

The cockpit voice recorder captured the stunned reaction of one pilot asking, “Why did you cut off the fuel?” The other pilot replied, “I didn’t.”

According to the report, both switches were then moved back to ‘RUN’. This triggered the aircraft’s automated engine relight systems. Engine 1 began to recover. Engine 2, however, could not sustain core speed, despite repeated fuel reintroductions. Six seconds after a “MAYDAY” distress call, all recording ceased. The plane crashed 0.9 nautical miles from the runway, killing 260 people.

At the crash site, both fuel switches were found in the ‘RUN’ position, consistent with the crew’s attempt to restart the engines midair. Investigators have found no evidence of sabotage or environmental interference. Weather was clear. No bird activity was reported.

Aviation experts say such switches cannot be easily triggered by accident. “No sane pilot would ever turn those switches off in flight,” said U.S. aviation analyst John Nance in a Reuters report. “The effect would be immediate.” Another expert, John Cox, in the same report noted the switches are independently wired and powered—making unintentional shutdown highly unlikely without a mechanical fault.

The aircraft was equipped with GE engines and used a switch model previously flagged in a 2018 FAA advisory for potentially faulty locking mechanisms. However, the advisory was not mandatory, and Air India did not conduct related inspections.

With the timeline now captured down to the second, the fuel switches—what they are, how they work, and why they moved—are now central to solving one of India’s worst aviation disasters.