Protesters are seen as Boeing President and CEO Dave Calhoun (Front) testifies during a Senate Committee on Homeland Security and Governmental Affairs hearing titled "Boeing's Broken Safety Culture" in Washington, D.C., the United States, on June 18, 2024. (Xinhua/Liu Jie)

WASHINGTON, June 18 (Xinhua) -- Boeing CEO Dave Calhoun was grilled by U.S. lawmakers in a Senate hearing on Tuesday over the air giant's growing safety and quality control crises.

"It's not enough for Boeing to shrug its shoulders and say, well, mistakes happen," Democratic Senator Richard Blumenthal, chair of a Senate subcommittee on investigations, said in his opening remarks.

"This is not an industry where it's okay to cut corners, to reduce inspections, to take shortcuts, and rely on broken parts that happen to be sitting around," Blumenthal said.

Among the audience are families of victims of the two crashes in 2018 and 2019 that killed 346 people, involving Boeing's 737 Max. Many came holding posters of loved ones who lost their lives in those tragedies.

Blumenthal also mentioned the incident in January when a door plug blew out of an Alaska Airlines Boeing 737 Max 9 shortly after takeoff. "The facade quite literally blew off the hollow shell that had been Boeing's promises to the world," he said.

Calhoun, who took charge in January 2020 following the two deadly crashes, defended the company's actions to try to improve manufacturing quality and restore its damaged safety reputation in recent years.

Senators also questioned the Boeing CEO over the company's treatment of whistleblowers.

Republican Senator Ron Johnson, ranking member of the subcommittee, said in the hearing that after whistleblower John Barnett raised his concerns about missing parts, "he reported that his supervisor called him 19 times in one day, and 21 times another day."

"When Barnett asked his supervisor about those calls, he was told, 'I'm going to push you until you break'," Johnson said.

Barnett, who testified in his whistleblower case against the troubled plane-maker, was found dead from a gunshot wound in his car in Charleston, South Carolina on March 9. A law enforcement investigation has concluded that the cause of death was suicide.

"Do you think Boeing has done enough today to make those kinds of corrections and what would you say to the whistleblowers who have come forward and face retaliation?" Johnson said.

"I asked myself that question every day. Have we done enough? "Calhoun said.

Republican Senator Josh Hawley criticized the Boeing CEO's compensation package of nearly 32.8 million last year, noting that it's a 45-percent increase from 2022.

"We've had multiple whistleblowers come before this committee and allege that Boeing is cutting every possible corner on quality and safety not just in the past, but now," said Hawley.

"They've alleged that you've eliminated safety inspections that there are fewer inspectors doing quality inspections out there. They alleged that when they raised quality issues and concerns, they were reassigned, they were retaliated against, they were physically threatened," Hawley continued.

In his response, Calhoun said the company has increased quality inspectors "significantly."

Calling on Boeing to change "a broken safety culture," Blumenthal said the plane-maker "needs to stop thinking about the next earnings call and start thinking about the next generation."