In the wake of the Air India flight that crashed moments after take off last week leaving just one survivor, two other Boeing 787s turned around shortly after taking off on June 16, one from Heathrow and another from Hong Kong.

Air India and Boeing are in the midst of significant turnarounds, but knowing the cause of the crash of Flight 171 will take a lengthy investigation.

An Air India crash Thursday involved a Boeing 787-8 Dreamliner, which the aircraft manufacturer first delivered 14 years ago.