The federal lawsuit was filed by the family of Samyo Stumo, who worked for the health systems development organization ThinkWell in Washington, D.C., and was among the 157 people who perished when the Ethiopian Airlines Boeing 737 Max 8 crashed last month shortly after taking off from Addis Ababa, the capital of Ethiopia.
The lawsuit filed in U.S. District Court in Chicago names Chicago-based Boeing, the manufacturer of the aircraft and Ethiopian Airlines as defendants. The suit also names Rosemount Aerospace Inc., the Delaware company that made the airplane's flight control system known as MCAS, which is now under scrutiny by investigators.
Nader phoned into a news conference Thursday morning that was held in Chicago by Stumo's parents, her brother and their lawyers, and called for a global boycott of the Boeing 737 Max 8, noting that the cash came just months after another 737 Max 8 flown by Lion Air crashed in Indonesia on takeoff, killing everyone aboard.
"If we don't get this right, if we don't end the cozy relationship between the patsy FAA, the captured agency, which has been documented for years, and the Boeing company, 5,000 of these fatally flawed planes will be in the air all over the world with millions of passengers," said the 85-year-old Nader. "An aircraft manufacturer, no matter what its past safety record, is not allowed two or more free disasters that are due to engineering misdesign of the Boeing 737 Max."
Nader blamed the back-to-back crashes of two new aircraft on a rush by Boeing management to compete with Airbus 320neo planes and said Boeing's engineers were "mercilessly pressured to speed up" in order to compete with Airbus.
"Those planes should never fly again. Those planes, the 737 Max 8, must be recalled," Nader said.
The lawsuit came just hours after Ethiopian Transport Minister Dagmawit Moges said preliminary findings from an investigation into the deadly crash show the aircraft had a valid certificate of airworthiness, the pilots were licensed and qualified to conduct the flight, and the plane's takeoff appeared to be "very normal." As the jet began nose-diving, the pilots "repeatedly" performed all emergency procedures provided by Boeing, but they "were not able to control the aircraft," Moges told reporters at a press conference in Addis Ababa.
Based on the initial report, Ethiopian safety investigators recommend Boeing review the aircraft flight control system of its new 737 Max 8 model and that aviation authorities verify the flight controllability has been adequately addressed by the manufacturer before resuming operations of this jet, according to the transport minister.
Ethiopian Airlines Flight 302 crashed in clear weather on the morning of March 10, six minutes after taking off from Addis Ababa Bole International Airport. The American-made jet, carrying 149 passengers and eight crew members, was headed to Nairobi, Kenya.
The air disaster came less than five months after a brand new Lion Air Boeing 737 Max 8 crashed minutes after taking off from Jakarta, the capital of Indonesia, killing all 189 people aboard, including three children.
The cause of the Oct. 29, 2018, Lion Air crash remains under investigation. The cockpit data recorder, which was recovered three days after the crash, showed that its airspeed indicator had malfunctioned on previous flights, investigators said.
A notice of claim was filed against the Federal Aviation Administration (FAA) on behalf on the Stumo family, the family's lawyer said. The notice is the first step before filing a lawsuit against the FAA and the federal agency has six months to respond before the Stumo family can file a formal lawsuit.
"They were responsible for assuring to the American public and to the world that the aircraft ... was safe for flight. It is pretty clear they failed in that regard," said a lawyer for the Stumo family, Kevin Durkin, of the Clifford Law Firm in Chicago.
Durkin said the FAA farmed out its responsibility of making sure a key component manufactured by Rosemount Aerospace Inc. called the maneuvering characteristic augmentation system, or MCAS, was safe.
"They delegated that responsibility to the manufacturer, Boeing, who had another motive of getting this aircraft out for sale," Durkin said. "They should not have delegated that responsibility ... and should have made their own independent determination that this system was safe."
Frank Pitre, another family attorney from the California law firm Cotchett, Pitre & McCarthy said the crash exposed "a symptom of a larger epidemic" in with regulatory agencies lacked the resources to adequately enforce compliance with safety regulations.
"Simply put, the watchdog can't do his job, so he just gives the fox the keys to the henhouse to count eggs," Pitre said.
In a statement to ABC News, Boeing officials said, "We won't comment on the lawsuit directly."
"Boeing extends our heartfelt condolences and sympathies to the families and loved ones of those onboard Ethiopian Airlines Flight 302," the company's statement reads. "As the investigation continues, Boeing is cooperating fully with the investigating authorities."
ABC News has also reached out to Rosemount Aerospace and Ethiopian Airlines for comment but have yet to receive a response from either company.
Samya Stumo parents, Michael Stumo and Nadia Millerron, and her brother, Adaan Stumo, fought through tears as they spoke at the news conference.
Micahel Stumo said his daughter was sent to Africa by her employer to open a new office in Uganda.
He said he and his family flew to Ethiopia as soon as they received word of the crash, hoping they would bring Samya home.
"Then we learned we would not bring home her body or even fragments of her body," the father said. " I stood on that Ethiopian and agricultural field with my family looking at the crater, feeling her. This should not happen to anyone again. That's why we're here."
Millerron described her only daughter as "fearless" and said she had a "radiant spirit that inspires others to live brightly and fully."
"We would all want to be like Samya, who was lighthearted. She brushed past negative and inconsequential comments and focused on what is good and what could get done," she said.
"Those in charge of creating and selling this plane did not treat Samya as they would their own daughters," she added. "We, as passengers, need to demand that planes be safe so no one else dies. Profits should not come before safety and we are making this effort here to help prevent a third crash."
The preliminary information released Thursday morning by the Ethiopian transport minister disputes reports that a foreign object, referred to as FOD by Ethiopian investigators, damaged Ethiopian Airlines Flight 302.
Two aviation sources familiar with the probe told ABC News that the Ethiopian Airlines flight suffered a damaged angle-of-attack sensor upon takeoff from a bird or foreign object, triggering erroneous data and the activation an anti-stall system — or the MCAS — sending the pitch of the plane downward and ultimately crashing into the ground.
According to the sources, the pilots did not try to electronically pull the nose of the plane up before following Boeing's emergency procedures of disengaging power to the horizontal stabilizer on the rear of the aircraft. One source told ABC News they manually attempted to bring the nose of the plane back up by using the trim wheel. Soon after, the pilots restored power to the horizontal stabilizer.
But Ethiopian Transport Minister Moges said Thursday that the investigation has yet to find any evidence of foreign object damage on the aircraft.
"The data provided by the FDR (flight data recorder) doesn't indicate that there is an FOD," Moges said.