Washington(CNN) A lawsuit filed by the former inspector general of the Department of Transportation accuses Boeing in a new lawsuit of repeatedly concealing design flaws in its aircraft and blaming pilots in the aftermath of crashes.
The suit, filed in federal court by former DOT inspector general Mary Schiavo on behalf of the estate of one of the victims in the Ethiopian Airlines crash, draws parallels between Boeing's responses in the aftermath of the 737 Max crashes in October and March and two crashes involving older 737 models in 1991 and 1994.
After both series of accidents, Boeing withheld information, rejected or resisted calls to ground the aircraft and emphasized pilots' faults over design issues, the lawsuit argues.
"Boeing deployed a common and continuous scheme after both series of crashes to conceal deadly faults in the aircraft that caused the planes, without pilot input or ability to overcome the aircraft, to dive into the ground killing all aboard," the lawsuit states.
Boeing spokesman Charles Bickers said the company won't comment on the lawsuit directly but that Boeing is cooperating fully with investigating authorities.
A Boeing software system known as MCAS, which pushes the nose of aircraft down if it senses an imminent stall, is believed to have played a role in crashes of Lion Air and Ethiopian Airlines jets in October and March in which a total of 346 people died.
Boeing's CEO Dennis Muilenburg said in April those 737 Max accidents occurred due to a chain of events and that the erroneous triggering of the MCAS software was one link in that chain.
In 1991 and 1994, previous models of the Boeing 737 crashed near Colorado Springs, Colorado, and Pittsburgh, respectively. A National Transportation Safety Board investigation found that the probable cause of the 1994 crash was loss of control of the airplane due to the plane's rudder moving to its maximum limit. The NTSB found that a rudder reversal "most likely occurred" in the 1991 incident as well.
The lawsuit states that Boeing had knowledge of similar 737 rudder incidents before those crashes but did not act on the reports.
In 1992, Boeing admitted at a meeting that part of the 737 did not meet the "fail safe design intent," but the company did not seek to ground the planes, according the suit and an attached exhibit that outlined the goals of that meeting.
Following the 1994 crash, Boeing then refused calls for design changes from the NTSB and instead recommended airlines provide additional training to enable pilots to counteract rudder deflections, according to the suit.
Schiavo, the attorney who brought the suit and a CNN aviation analyst, said she found Boeing's responses to the recent 737 Max crashes similar to the company's response to the previous incidents when she worked for DOT.
"We seem to be reliving history and I would have thought that we would have learned the lesson," Schiavo told CNN. "When you have a plane nosedive out of the sky, you better put safety ahead of profits because you can't be sure that another one won't happen."
The lawsuit adds to others filed against Boeing in the aftermath of the 737 Max crashes, including a wrongful death suit brought by the family of an American woman who died in the Ethiopian Airlines crash.
Last week, Boeing said it has finished the development of a software fix for the 737 Max, but that update has not yet been certified by the Federal Aviation Administration, which must happen before the agency allows the plane to fly in the US again.
On Thursday, international regulators will meet in Fort Worth, Texas, with the FAA to discuss the reviews of the 737 Max.
Aviation regulators in other countries will complete their own reviews or validations of the plane's updated software separate from the FAA's reviews, which raises the possibility flight restrictions could be lifted in some countries but not in others.