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 Air India flight, carrying 242 passengers and crew members, crashed shortly after takeoff from Ahmedabad, India, en route to London Gatwick.

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

The crash happened just weeks after the company cut a deal with the U.S. government to avoid taking criminal responsibility for a pair of deadly crashes in 2018 and 2019.