National consumer advocate Ralph Nader on Thursday called for the permanent grounding of Boeing 737 Max airplanes, the same day lawyers filed a lawsuit in Chicago against Boeing on behalf of Nader’s great-niece who died in the crash of Ethiopian Airlines Flight 302.

“Those planes should never fly again. Those planes — the 737 Max 8 — must be recalled,” said Nader, speaking by phone as the family of his niece sat in the downtown offices of Clifford Law, the firm that has filed a federal suit against Boeing, Ethiopian Airlines and Rosemount Aerospace, which made the sensors at the center of the investigation.

The lawsuit alleges, among other things, that “Blinded by its greed, Boeing haphazardly rushed the 737 Max 8 to market, with the knowledge and tacit approval of the United States Federal Aviation Administration … while Boeing actively concealed the nature of the automated (flight control) system defects.”

At the time, according to the suit, Boeing executives were worried about losing business to Airbus, its chief competitor, and that company’s more fuel-efficient A320 neo.

Nader said: “Boeing executives pushed its engineers to press an aging design beyond its limits.”

Nader’s niece, Samya Stumo, 24, was based in Washington, D.C., working for a nonprofit global health organization. When she died March 10, she was in the process of setting up new offices in Uganda for her agency.

Her father, Michael Stumo, described the anguish of being in Ethiopia and seeing the crater where his daughter’s remains lay amid the destroyed aircraft.

“Then we learned we could not bring home her body or even fragments of her body,” Stumo said.

A preliminary report released Thursday by the Ethiopian government said the Ethiopian Airlines jet suffered from faulty readings by a key sensor, and pilots followed Boeing’s recommended procedures when the plane started to nosedive but could not avoid crashing.

The findings including the faulty sensor data drew the strongest link yet between the crash in Ethiopia and an October crash off the coast of Indonesia, which both involved Boeing 737 Max 8 jetliners. All 346 people on the two planes were killed.

Both planes had an automated system that pushed the nose down when sensor readings detected the danger of an aerodynamic stall, but it now appears that sensors malfunctioned on both planes.

In a statement, Boeing repeated that it is working on a software update to prevent the automated system from activating when it should not.

“I’d like to reiterate our deepest sympathies are with the families and loved ones of those who lost their lives in the accident,” Boeing Commercial Airplanes President and CEO Kevin McAllister said in a statement issued Thursday.

“We thank Ethiopia’s Accident Investigation Bureau for its hard work and continuing efforts. Understanding the circumstances that contributed to this accident is critical to ensuring safe flight. We will carefully review the AIB’s preliminary report, and will take any and all additional steps necessary to enhance the safety of our aircraft.”

MORE ABOUT THE BOEING 737 MAX

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• Boeing to standardize safety feature on troubled 737 Max jets

Contributing: The Associated Press