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The Charleston County Coroner's Office told the BBC that John Barnett, 62, died from a self-inflicted wound on Saturday. According to the BBC, Barnett was cross-examined by Boeing's lawyers and his own attorney days before he died.
The court planned for Barnett to answer more questions on Saturday, but he did not appear as planned.
The BBC reported that he was later found dead in his truck, which was parked in a hotel parking garage.
Barnett was employed by Boeing for over three decades before retiring in 2017. He worked as a quality control engineer at the company.
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In 2019, Barnett told the BBC that Boeing would rush to get its 787 Dreamliner jets off the production line, compromising safety.
He alleged the emergency oxygen systems that were made for 787 Dreamliners had a failure rate of 25%. This meant that a quarter of 787 Dreamliners had the potential to rapidly lose oxygen if the cabins were suddenly decompressed, suffocating passengers.
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Barnett said that he had encountered these issues when he began working at Boeing's North Charleston plant in 2010. He reportedly raised his concerns to his managers, but did not see them take any action.
The Federal Aviation Administration reviewed Boeing in 2017 and ordered the company to take action, which corroborated some of Barnett's allegations.
Boeing told FOX Business that the company was saddened by Barnett's death.
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"We are saddened by Mr. Barnett’s passing, and our thoughts are with his family and friends," Boeing's statement read.
FOX Business reached out to the Charleston County Coroner's Office for more information.
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