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.

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

The troubling cockpit dialogue revealed in a preliminary report into the June 12 crash of Air India flight 171 – which killed all but one of the 242 passengers on board – is likely to haunt investigators,