An official report on the world’s deadliest aviation accident in a decade, seen by CNN, has answered one key question – but raised others.

Crash investigators, fresh from combing through the wreckage of Air India Flight AI171, have released a short, 15-page report clarifying the facts around the disaster

A preliminary report depicted confusion in the cockpit shortly before an Air India jetliner crashed, killing more than 200 people last month, after the plane's engine fuel cut-off switches almost simultaneously flipped off,