An aircraft mechanic who was contracted to repair Boeing planes has alleged he was labelled a "snitch" and then sacked for speaking up over safety concerns.
Richard Cuevas claimed he witnessed substandard manufacturing and maintenance work on a crucial section of Boeing 787 aircraft.
Boeing, which has been dogged by questions over whether its safety culture is rigorous enough, said the issues had been investigated and "did not present a safety concern".
Lawyers representing Mr Cuevas alleged he reported critical issues that could create a serious public safety risk and have filed complaints with the Federal Aviation Administration and the Occupational Health and Safety Administration.
Mr Cuevas, who has worked in the aviation industry for 40 years, was contracted to Spirit Aerosystems, to work on Boeing's 787 forward pressure bulkhead, a dome at the nose of the aircraft which serves as a barrier.