In the days before his death, he had been giving evidence in a whistleblower lawsuit against the company.
Boeing said it was saddened to hear of Mr Barnett’s passing.
At the time of his death, Mr Barnett had been in Charleston for legal interviews linked to that case.
Last week, he gave a formal deposition in which he was questioned by Boeing’s lawyers, before being cross-examined by his own counsel.
He had been due to undergo further questioning on Saturday. When he did not appear, enquiries were made at his hotel.
About the only non-snark thing I could say was that Boeing could’ve just given him a free flight on a non-upgraded 737-MAX with the original software if they wanted that outcome and plausible deniability.