The investigation into Air India flight 171 crash opens up questions into the many concerns surrounding Boeing's 787.

Last year, the F.A.A. said it was also investigating claims by a Boeing engineer that parts of the fuselage, or body, of the Dreamliner were improperly fastened together, which the whistle-blower said could cause premature damage to the plane over years of use.

The aircraft manufacturer has been under scrutiny for the last few years regarding safety after manufacturing issues caused two fatal crashes and other incidents.