A preliminary report on the investigation into the Air India flight that crashed last month has answered some questions about the fatal accident but raised many more and fuelled speculation about the cause.

The report and India’s inspection order referred to an advisory from the Federal Aviation Administration in 2018 that recommended that carriers using Boeing models, including the 787, inspect the locking mechanism of the fuel control switches to ensure they could not be moved accidentally.

Air India's inspection of the locking feature on the fuel control switches of its existing Boeing 787 aircraft found no issues, an internal communication circulated within the airline said."Over the weekend,