Why did you cut off?” one of the pilots asked, as the cockpit voice recorder picked up the bewilderment that would come to characterize the worst air tragedy in a decade. The initial probe of Air India Flight 171’s fatal crash on June 12,

The U.S. Federal Aviation Administration and Boeing have privately issued notifications that the fuel switch locks on Boeing planes are safe.

Apparent gaps in AAIB’s preliminary report means that while a key factor in the disaster—cutting of the fuel supply—has been confirmed, not much else has. FAA’s insistence that the accident does not change its evaluation of the fuel switch problems counters the only switch-related technical issue discussed in the report.