By David Shepardson and Allison Lampert

WASHINGTON (Reuters) - Boeing CEO Dave Calhoun will tell a U.S. Senate committee on Tuesday that the planemaker understands concerns about its safety culture after a January mid-air emergency involving an Alaska Airlines 737 MAX 9 raised widespread alarm.

"Much has been said about Boeing’s culture. We’ve heard those concerns loud and clear. Our culture is far from perfect, but we are taking action and making progress," Calhoun will tell the Senate Permanent Subcommittee on Investigations, according to his written statement first reported by Reuters. "I know full well that this is an industry where we simply must get it right, every time."

Since the Jan. 5 mid-air blowout of a door plug on a 737 MAX 9 jet, scrutiny of the planemaker by regulators and airlines has intensified. Boeing has shaken up management and Calhoun said in March that he will step down by year-end.

"Boeing must repair a broken safety culture and that is management's task ahead," said Senator Richard Blumenthal, a Democrat who chairs the panel holding Tuesday's hearing. "It should have been done long ago."

He noted that the MAX 8 suffered two fatal crashes in 2018 and 2019 that killed 346 people. "Boeing has lost its luster and indeed its reputation for excellence as a result of self-inflicted wounds," Blumenthal said.

He said a new whistleblower will come forward in the next day after he held a hearing with a prior whistleblower in April.

The National Transportation Safety Board said four key bolts were missing from the Alaska Airlines plane. The Justice Department has opened a criminal investigation into the January incident.

"In our factories and in our supply chain, we took immediate action to ensure the specific circumstances that led to this accident would not happen again," Calhoun's testimony says. "I understand the gravity of Boeing’s role in upholding the integrity of aerospace safety in our industry."

Boeing is in talks to reacquire Spirit AeroSystems, the manufacturer of the 737 MAX fuselage.

Last week, Michael Whitaker, head of the Federal Aviation Administration, said the agency was “too hands off” in its oversight of Boeing before the Jan. 5 accident.

On May 30, Boeing delivered a comprehensive quality improvement plan to the FAA after Whitaker in late February gave the company 90 days to develop a comprehensive plan to address "systemic quality-control issues." He has barred the company from expanding production of the MAX.

Calhoun said the plan has "specific metrics, which we will use to hold ourselves accountable and the FAA will use to provide the oversight required."

(Reporting by David Shepardson in Washington and Allison Lampert in Montreal; Editing by Matthew Lewis)