A cockpit voice recording of doomed Air India Flight 171 indicates the younger co-pilot asked his more experienced colleague why he turned off the plane’s fuel-supply switches, according to people familiar with the matter.

The deadly Air India crash has renewed a decades-old debate in the aviation industry over installing video cameras to monitor airline pilot actions.

A preliminary report released last week included detail about the fuel, saying that the fuel to the plane's engines appeared to have been shut off.