A preliminary investigation released last week by India's Aircraft Accident Investigation Bureau found confusion in the cockpit shortly before the June 12 crash, and raised fresh questions over the position of the critical engine fuel cutoff switches.

A preliminary assessment in last month’s disaster focusing on fuel being cut to both engines only deepened the mystery for people grieving loved ones.

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.