Boeing admitted Thursday that a faulty sensor in its anti-stall system played a part in last month's deadly Ethiopian plane crash.

Ethiopian investigators released their preliminary report into the disaster that killed 157 people, saying the anti-stall system kept pushing the nose of the plane downward shortly after takeoff as the pilots struggled to take control.

Ethiopia's transport minister said the pilots flying the Boeing 737 MAX 8 "performed all the procedures repeatedly provided by the manufacturer but was not able to control the aircraft."

The initial findings about the faulty sensor are almost identical to the suspected cause of the crash of an Indonesian 737 MAX 8 in October, killing 189 when the plane dropped into the Java Sea.

Boeing CEO Dennis Muilenburg expressed his sorrow over the loss of life, and said new software that will be installed on all the grounded MAX 8s will fix the problem.

"It's our responsibility to eliminate this risk. We own it, and we know how to do it," he said.

Boeing said the software will add several layers of protection against faulty readings and will also come with "associated comprehensive pilot training."

Federal regulators in the U.S. and those around the world must approve the new software before it can be installed.

Lawsuit against Boeing

Meanwhile, relatives of famed U.S. consumer advocate Ralph Nader, whose niece Samya Stumo was among the victims of the Ethiopian crash, have filed a lawsuit against Boeing.

Stumo's family charged Boeing, Ethiopian Airlines and parts manufacturer Rosemount Aerospace with negligence and civil conspiracy.

"Those planes should never fly again," Nader said Thursday. "If we don't end the cozy relationship between the patsy FAA [Federal Aviation Administration] and the Boeing company, 5,000 of these fatally flawed planes will be in the air all over the world with millions of passengers."

Nader was referring to the FAA's process that certifies planes for flying and allowing Boeing to take some of that responsibility itself, under FAA supervision.

The Justice Department, Transportation Department, and Congress are probing the FAA's certification process. They are also looking into why Boeing did not immediately ground the MAX 8 after the Indonesian crash. (VOA)

• A Boeing 737 MAX sits outside the hangar during a media tour at the Boeing plant in Renton, Washington.

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