Boeing whistleblower who warned of aircraft safety flaws found dead
A Boeing 737 MAX sits outside the hangar during a media tour of the Boeing 737 MAX at the Boeing plant in Renton, Washington.

Barnett, known as Mitch to his family and "Swampy" to his friends, had worked at Boeing's 787 plant in Charleston, South Carolina, since 2010, his family said.

In a statement Monday, ​Boeing said: ​​"We are saddened by Mr. Barnett's passing, and our thoughts are with his family and friends." NBC News has asked Boeing for comment on the allegations in the Barnett family's statement.

The statement from Barnett's family said he had suffered from post-traumatic stress disorder and anxiety attacks and that the "hostile work environment at Boeing" led to his death.

Charleston County Coroner Bobbi Jo O'Neal said in a statement Monday that Barnett died "from what appears to be a self-inflicted gunshot wound," in the South Carolina city on Saturday.

His family said in a statement Monday that he had tried to highlight serious concerns but was met with "a culture of concealment" that valued "profits over safety."

John Barnett, 62, spent more than three decades at the aircraft manufacturing giant and sounded the alarm with aviation authorities in 2017 over what he said were potentially "catastrophic" safety failings.

A former Boeing quality inspector who filed a whistleblower complaint over alleged plane safety flaws was found dead "from what appears to be a self-inflicted gunshot wound," officials in Charleston, South Carolina, said Monday.

In 2019, The New York Times interviewed several former Boeing employees about their safety concerns. Barnett told the paper that metal shavings — created when metal fasteners are screwed into nuts — could potentially cut wiring that connects the flight controls.

The FAA ordered Boeing to clear the shavings from the Dreamliners in 2017. Boeing said then that it was following the ruling and would look to improve the design of the nut, but also said it wasn't a flight safety issue.

But Barnett told The Times: "I haven't seen a plane out of Charleston yet that I'd put my name on saying it's safe and airworthy."

After his retirement in 2017, Barnett filed a whistleblower complaint to federal regulators about his experiences at the South Carolina plant. He also launched a separate legal action against Boeing, accusing the company of denigrating his character and hampering his career. Boeing denied the allegations.

His case was up for trial this June, the family statement said, adding: "He was looking forward to having his day in court and hoped that it would force Boeing to change its culture."

While Barnett loved his work for most of his career, in Charleston "he learned that upper management was pressuring the quality inspectors and managers to cut corners" and not to follow legally-required safety processes, the statement said.

He alleged that staff were pressured not to document defects because it would slow down the assembly line, it added.

"John told us that every day was a battle to get management to do the right thing," the family said. The statement added that Barnett and others who highlighted problems were labeled as "trouble-makers," whereas previously the company had rewarded those who discovered defects.

"It caused John so much stress that his doctor told him that if he stayed, he would have a heart attack," the family said.

"Mitch was fun-loving, and totally devoted to family, especially his nieces and nephews and great nieces and nephews," an obituary shared by the family said.

It added that he is survived by his mother, Vicky Melder Stokes; brothers, Mike Barnett, Robbie Barnett, and Rodney Barnett; eight nieces and nephews and 11 great-nieces and nephews.

The news comes as Boeing faces regulatory and public scrutiny over a series of incidents involving its planes.

A Justice Department investigation has been opened after a door plug blew out on an Alaska Airlines flight in January which led to the temporary grounding of some Boeing 737 Max 9 airplanes, although they have since returned to the air.

And on Monday, 50 people were injured on a Boeing Dreamliner plane after a sudden movement mid-air, on a flight from Sydney to Auckland, New Zealand.

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