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,

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.

With conclusive information hard to come by weeks after the fatal Air India crash, the aviation industry has shifted its focus to possible pilot error.