A Boeing whistleblower who was found dead in a hotel car park scrawled his final frenzied words denouncing the air travel giant in his notebook.

John Barnett's body was found inside his Dodge Ram on March 9, the same day he was due to testify against Boeing. The 67-year-old was found with a note on his passenger seat that read ''F*** Boeing'' outside a Holiday Inn just days after first testifying in a bombshell lawsuit against the plane production company.

The note slamming Boeing continued: ''America. Come together or die!! I pray the motherf***** that destroyed my life pay!!! I pray Boeing pays!!! Bury me face down so Boeing and their lying-a** leaders can kiss my a**.''

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The eerie note Boeing Whistleblower John Barnett left before he was found dead in car park (
Image:
Charleston Police Department)

John's mother told investigators her son would often make these remarks. John then appeared to say that whistleblowers were not offered enough protection, writing: ''Whistleblowers protection is f***** up too! And I wasn't stoned when I wrote this...Really!''

Authorities said they authenticated the handwriting as John's and only his fingerprints were found on the notebook. A coroner has now said John's death “is best deemed, 'suicide'' after the Charleston Police Department concluded he died of a “self-inflicted gunshot wound”.

John also sent final words to his closest friends and family in the note: “To my family and friends, I found my purpose. I’m at peace. I love you more.”

His body was found the day he was due to testify against Boeing after alleging under-pressure workers were deliberately fitting sub-standard parts to aircraft on the assembly line. Charleston Police Department announced the conclusion of its investigation into his death on Thursday.

John made sure to send a final word to his loved ones (
Image:
Charleston Police Department)

John worked for Boeing for 32 years, until his retirement in 2017. In the days before his death, he had been giving evidence in a lawsuit. He gave a formal deposition and was questioned by Boeing's lawyers, before being cross-examined by his own counsel.

The report from Charleston County Coroner Bobbi Jo O'Neal said: “All findings were consistent with a self-inflicted gunshot wound.” The police report stated he had shown symptoms of “post-traumatic stress disorder, anxiety, sadness, fear of impending death of others and intrusive thoughts.”

Investigators found him alone inside his car with the key to his hotel room in his pocket and a handgun he illegally purchased in 2000 in his car. There were no signs of forced entry or physical struggle.

The company has been under intense scrutiny in recent months due to a number of issues on its planes, including when a door plug blew out during an Alaska Airlines flight in January. A preliminary report from the US National Transportation Safety Board suggested that four key bolts, designed to hold the door securely in place, were not fitted

He was due to undergo further questioning, however, after failing to show up for the second part of his testimony, inquiries were made and he was found dead by hotel employees during a welfare check.

After learning of his death, Johen's lawyer Brian Knowles told Corporate Crime Reporter: "Today is a tragic day. John had been back and forth for quite some time getting prepared. The defence examined him for their allowed seven hours under the rules on Thursday. I cross-examined him all day yesterday (Friday) and did not finish.

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"We agreed to continue this morning at 10 a.m. (co-counsel) Rob (Turkewitz) kept calling this morning and his (John's) phone would go to voicemail. We then asked the hotel to check on him. They found him in his truck dead from an 'alleged' self-inflicted gunshot. We drove to the hotel and spoke with the police and the coroner."

Surveillance footage captured John entering the hotel at 7.36pm on March 8 and he was last seen exiting the building at around 8.30pm. CCTV also showed John's truck reversing into a parking space at 8.45pm. Police said throughout the night there was no video evidence of anyone near his vehicle, which remained in the same spot.