Officials said they had found the cockpit voice recorder that may provide crucial clues about what caused the Air India flight to crash, killing at least 270 people.

Air India's Chairman N. Chandrasekaran on Monday told staff that last week's plane crash that killed at least 271 people should be a catalyst to build a safer airline, urging employees to stay resolute amid any criticism.

An Air India pilot turned back his Delhi-bound Boeing 787-8 Dreamliner to Hong Kong airport as a precaution shortly after taking off on Monday, citing a technical issue, Indian media reported. Flight tracking data showed the pilot turning Flight AI315 around less than 30 minutes into the flight from Hong Kong.

Close on the heels of the mishap involving an Air India flight from Ahmedabad to London Gatwick, a domestic flight of the airline carrying 168 passengers developed a technical issue immediately after take-off from Delhi to Vadodara on Sunday evening.

All but one of the 242 people on board the London-bound flight died when it crashed into a residential area in Ahmedabad shortly after take-off.

Vishwash Kumar Ramesh, a British national, appears to be the only survivor of Air India flight 171, which crashed with 242 people aboard.

More than 240 people were killed when an Air India plane bound for London crashed moments after taking off from the city of Ahmedabad on Thursday, authorities said, in the world's worst aviation disaster in a decade.