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.

Singapore Airlines on Tuesday said all fuel switches on its Boeing 787 aircraft -- as well as those belonging to its subsidiary Scoot -- are functioning properly in compliance with regulatory requirements.

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.