Investigators are probing the wreckage and cockpit recorders to understand what went wrong just after take-off. The Air India flight climbed to 625 feet in clear weather before losing location data 50 seconds in, per Flightradar24. Saturday's 15-page report offers early insights.

Following is a timeline of key events in the investigation to date: An Air India Boeing 787 Dreamliner bound for London crashes shortly after takeoff from Ahmedabad city, killing all but one of the 242 people on board.

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