A former Spirit AeroSystems quality manager is alleging that the supplier knowingly delivered defective 737 Max fuselages to Boeing for years.

Speaking to CBS News, Santiago Paredes detailed his work at Spirit Aerosystems' factory in Wichita, Kansas, where he inspected 737 fuselages before they were sent to Boeing. Spirit AeroSystems was spun off from Boeing in 2005, and is responsible for building most of the 737 Max line. Paredes spent a decade with Spirit before leaving in 2022, where he claims "it was very rare for us to look at a job and not find any defects," and that he was told to downplay any issues he found.

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"Working at Spirit, I almost grew a fear of flying," he said. "Knowing what I know about the 737, it makes me very uncomfortable when I fly on one of them."

Paredes further alleged that Boeing was aware Spirit was delivering the defective fuselages, and that it was "just a matter of time before something bad happened," referencing a blown-out door plug aboard a 737 Max 9 in January. CBS News also received several images from current and former Spirit workers showing dented fuselages and missing fasteners. 

In response to Paredes' claims, a Spirit spokesperson told CBS News that the company "encourages all Spirit employees with concerns to come forward, safe in knowing they will be protected." 

"We remain committed to addressing concerns and continuously improving workplace safety standards," he added. 

This comes nearly a month after whistleblower Sam Salehpour stepped forward with claims that fuselages for Boeing 787 Dreamliners weren't fastened together correctly, and that the planes were at risk of breaking apart over time. Then on May 7, the Guardian reported that the Federal Aviation Administration was investigating whether Boeing completed inspections for 787 Dreamliners to confirm that fuselages were correctly attached, and if employees might have falsified records.