Fuel switches of the Boeing 787 Dreamliner have come under scrutiny after a preliminary crash report raised questions about how the controls were moved from the "run" to "cutoff" position, starving the engines of fuel.

The two engines on the Air India flight shut down within one second of each other before the Boeing 787 Dreamliner crashed last month in Ahmedabad, India, killing at least 260 people, according to a preliminary report released Friday.

Indian investigators determined the Boeing 787 Dreamliner was properly configured and lifted off normally. But three seconds after takeoff, the engines' fuel switches were cut off.