"External reports draw similarities between this incident and the Lion Air Flight 610 incident on October 29, 2018," the FAA said in its statement. "However, this investigation has just begun and to date no data have been provided to draw conclusions or take action."
Popular planes are a key profit factor for Boeing, whose commercial air business produced almost 60% of its over $ 100 billion in revenue last year.
US airlines have tried to calm travelers' concerns about aircraft being safe.
While it is very unusual to have two fatal accidents of new aircraft so close, analysts have warned that it is too early to know the cause of the Ethiopian Airlines accident or whether it is entirely related to the crash of the Lion Air flight. year.
The crash of the Lion Air Flight 610 in October drew attention to the maneuvering feature enhancement system, known as MCAS, which is included in the new aircraft and a system that officials said they believed had repeatedly pushed the nose of the plane down.
A position in the bow is the way to recover from a stall but it can be catastrophic if the plane signals that it is in a stall when it is not. Boeing issued a security bulletin for pilots in November, telling them how to handle if the nose of the plane is automatically lowered.
The FAA announced in its Monday note that it plans to impose improvements to the design of the automatic and signaling system on board Boeing aircraft by April 2019. Boeing is planning to update the training and manual requirements along with these changes, the DO.
Dennis Tajer, a pilot of the Boeing 737 and spokesman for the Allied Pilots Association, which represents the pilots of the American Airlines, said the company's pilots met Boeing staff following the Lion Air crash and that the pilots did not they had been informed of the new system before the Lion Air crash. Tajer said Boeing's response answered questions about the new system.
The FAA notice applied to both the Boeing 737 MAX 8 and the larger MAX 9 variant. There are 74 of these aircraft in the US fleets and 374 worldwide, the agency said.
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