The U.S. Department of Transportation is investigating the Federal Aviation Administration’s approval of Boeing Co.’s 737 Max jetliners, according to people familiar with the probe, an unusual inquiry into potential lapses in federal safety approvals for new aircraft.
The inquiry focuses on a safety system that has been implicated in the Oct. 29 Lion Air crash that killed 189 people, according to a government official briefed on its status. Aviation authorities are looking into whether the anti-stall system may have played a role in last week’s Ethiopian Airlines crash, which killed all 157 people on board.
On Sunday, Ethiopia’s transport minister, Dagmawit Moges, said there were “clear similarities” between the two crashes. U.S. officials cautioned that it was too early to draw conclusions because data from the black boxes of the Ethiopian Airlines plane still need to be analyzed.
The two crashes have sparked the biggest crisis Boeing
has faced in about two decades, threatening sales of a plane model that has been the aircraft giant’s most stable revenue source and potentially making it more time consuming and difficult to get future aircraft designs certified as safe to fly.
The Transportation Department’s inquiry was launched in the wake of the Lion Air accident and is being conducted by its inspector general, which has warned two FAA offices to safeguard computer files, according to people familiar with the matter. The internal watchdog is seeking to determine whether the agency used appropriate design standards and engineering analyses in certifying the anti-stall system, known as MCAS.
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