Built to resist errors, then how did Air India 171’s fuel switches flip midair? Here’s what we know

The preliminary report into the Air India flight 171 crash says both engine fuel control switches moved to the “cutoff” position within seconds of takeoff, causing the plane’s engines to lose thrust. 

The report does not assign blame but notes that cockpit voice recordings captured one pilot asking the other, “Why did you cutoff?”—with the other denying doing so. Though the switches were quickly flipped back to “RUN,” one engine briefly reignited, but it was too late to prevent the crash.

The incident has focused attention on a scenario: how such a critical function could be triggered mid-flight in one of the most advanced commercial jets in service. It has also raised questions about cockpit design, safety mechanisms, and whether such a shutdown could occur without deliberate intent.

What are the fuel control switches?

Function: These switches regulate the flow of fuel to each engine. They’re used during engine start and shutdown, and in rare cases, to control the engines in flight.

Location: On the Boeing 787, they are located directly beneath the thrust levers, inside a dedicated fuel control module.

Operation: Each switch has two settings—“RUN” to supply fuel, and “CUTOFF” to stop it. When set to “CUTOFF,” the engine shuts down.

Built-in safety mechanisms:

Switches are spring-loaded to resist unintended movement.

To engage “CUTOFF,” a pilot must lift the switch over a metal stop lock.

Guard brackets on either side prevent accidental contact.

Could they have been moved by accident?

The design suggests otherwise. Aviation experts and the Air India report stress that the switches require a deliberate action to move.

John Cox, a U.S. aviation safety expert, told Reuters, “You can’t bump them and they move.”
John Nance added in the same Reuters report, “No sane pilot would ever turn those switches off in flight,” particularly during climb-out.

No proof of fault

According aviation website, The Air Current, investigators found no mechanical defect or design flaw in the switches or their locking mechanisms. The system is intentionally built to prevent accidental activation, and there is no known precedent of both switches being inadvertently moved mid-air on a 787.

What remains unknown

The investigation is ongoing. The preliminary report, along with The Air Current’s analysis, states it is still unclear whether the switches were moved intentionally, inadvertently, or due to some other factor.