The black boxes will provide cockpit conversations and data related to the plane's engine and control settings to investigators and help them in determining the cause of the crash.

India's aviation safety watchdog has asked Air India for the training records of the pilots and dispatcher for the plane that crashed last week as part of its investigation into the incident that killed at least 271 people,

There have been cases of a very small number of survivors in very serious accidents, but it is "very rare" for there to be only one, a professor told Newsweek.