New whistleblower testimony in a Senate report released late Monday alleges that Boeing Co. has a history of attempting to “eliminate quality inspections” and mishandling damaged parts, sparking concern among senators that the aircraft manufacturer prioritizes production over safety.

The preliminary report, arising from a Senate Homeland Security Investigations Subcommittee investigation into the company, cast a shadow over Boeing CEO Dave Calhoun’s appearance Tuesday on Capitol Hill.

“It’s not enough for Boeing to shrug their shoulders and say ‘Well, mistakes happen.’ This is not an industry where it’s okay to cut corners, to reduce inspections, to take shortcuts and rely on broken parts that happened to be sitting around,” subcommittee Chair Richard Blumenthal, D-Conn., said during the hearing. “It is not an industry where it’s okay to rush planes out the door.”

The report follows increased scrutiny of the aircraft manufacturer following a mid-flight door plug blowout on a 737 Max 9 plane in January. A Federal Aviation Administration audit, as well as a report from a panel commissioned by the FAA, found safety culture and manufacturing quality concerns at the company.

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Sam Mohawk, a current Boeing quality assurance investigator at the Renton, Wash., facility, detailed how the 737 program was losing track of “hundreds” of nonconforming, or damaged, parts despite mandates requiring aircraft manufacturers to keep tight records, according to the report. Those parts can’t be used on an aircraft without special permission.

Mohawk this month filed a complaint with the Occupational Safety and Health Administration alleging the company retaliated against him, which was released publicly as part of the subcommittee report. In it, he said he believed “many of the missing parts were unlawfully installed on aircraft.” He also alleged that the company intentionally hid improperly stored parts from the FAA during an inspection, and that he was directed by his superiors to “cancel” records that designate a part as noncomforming.

The report also included a statement from Merle Meyers, a former Boeing quality manager at the Everett, Wash., factory, who said he was particularly troubled that workers at that factory “felt such pressure to keep production moving that they would find unauthorized ways to get the parts they needed.”

Another whistleblower, John Barnett, who was a quality manager in Charleston, S.C., also alleged the company’s handling of non-conforming parts was concerning and that, when he reported concerns, he was ignored or told to find “ways to work in the gray areas to help manufacturing out.”

The investigation also cited FAA enforcement letters from 2016 to 2021 as well as other whistleblower testimony that found Boeing engaged in a “repeated, years-long” effort to eliminate quality inspections, instead relying on workers to inspect their own work.

In May, after Boeing vowed to boost safety culture in the wake of the January incident, the FAA opened a new investigation into the company for potentially failing to complete required inspections on 787 aircraft while falsely recording those inspections as being completed, the subcommittee report said.

‘Far from perfect’

Although Calhoun has attended private meetings with senators on Capitol Hill this year, the Tuesday hearing was his first public appearance in front of lawmakers since the January incident.

Calhoun touted new safety plans at the hearing but acknowledged the company’s “far from perfect” safety culture.

“Much has been said about Boeing’s culture. We’ve heard those concerns loud and clear … but we are taking action and making progress,” he said. “We understand the gravity, and we are committed to moving forward with transparency and accountability, while elevating employee engagement.”

Calhoun pointed to an action plan, which the FAA required the company to complete, that aims to address safety culture concerns. He lauded Boeing’s “comprehensive look” at its quality and manufacturing systems and adds that the company has “listened to our employees” and brought in an independent quality expert to assess its processes.

But senators were not fully convinced, as more whistleblowers — now over a dozen, Blumenthal said — stepped forward during the course of the subcommittee investigation.

“You’re not focused on safety, you’re not focused on quality, you’re not focused on transparency … you’re focused on exactly what you were hired to do, which is that you’re cutting corners,” Sen Josh Hawley, R-Mo., said during the hearing. “And you’re being rewarded for it — you got a huge raise.”

“You’re the problem,” Hawley added.

Calhoun said earlier in the hearing that he has not personally spoken to whistleblowers but said Boeing has an “ethics team” to probe each whistleblower claim. He also could not answer how many employees have been fired after they were found to retaliate against a complainant, but added that “there are some.”

“We have a [safety] process, it works,” Calhoun said.

“I beg to differ, it’s not working,” Blumenthal said, interrupting Calhoun. “You know it’s not working.”

Blumenthal added that the Justice Department will “conclude” the subcommittee investigation and make an independent decision about whether to prosecute.

“Regardless of that decision, this is a moment of reckoning and an opportunity to change a broken safety culture,” he said.

Calhoun announced in March that he will step down at the end of the year as part of a management shake-up following the January incident. But he’s likely to be back on Capitol Hill before then, as Senate Commerce Chair Maria Cantwell, D-Wash., who is also scrutinizing Boeing and the FAA, said last week she intends to call for Calhoun to appear.

Commerce Committee ranking member Ted Cruz, R-Texas, said at a hearing last week that he wants to hear directly from Boeing on how the company will address production failures.

“We have a responsibility as the committee of jurisdiction for civil aviation to conduct oversight on these matters and trust we will soon hear from Boeing execs,” Cruz said.