September 16:

The two fatal crashes that killed 346 people aboard Boeing’s 737 Max and led to the worldwide grounding of the plane were the “horrific culmination” of engineering flaws, mismanagement and a severe lack of federal oversight, the Democratic majority on the House Transportation and Infrastructure Committee said in a report on Wednesday.

The report, which condemns both Boeing and the Federal Aviation Administration for safety failures, concludes an 18-month investigation based on interviews with two dozen Boeing and agency employees and an estimated 600,000 pages of records. Over more than 200 pages, the Democrats argue that Boeing emphasized profits over safety and that the agency granted the company too much sway over its own oversight.

“This is a tragedy that never should have happened,” Representative Peter A. DeFazio of Oregon, the committee chairman, said. “It could have been prevented, and we’re going to take steps in our legislation to see that it never happens again.”

Representative Sam Graves of Missouri, the committee’s top Republican, said that while change was needed, congressional action should be based on nonpartisan recommendations, “not a partisan investigative report.”

The report was issued as the F.A.A. appeared close to lifting its grounding order for the Max after test flights this summer. F.A.A. clearance could lead aviation authorities elsewhere to follow suit and allow the plane to fly again as soon as this winter.

The congressional report identified five broad problems with the plane’s design, construction and certification. First, the race to compete with the new Airbus A320neo led Boeing to make production goals and cost-cutting a higher priority than safety, the Democrats argued. Second, the company made deadly assumptions about software known as MCAS, which was blamed for sending the planes into nosedives.

Third, Boeing withheld critical information from the F.A.A. Fourth, the agency’s practice of delegating oversight authority to Boeing employees left it in the dark. And finally, the Democrats accused F.A.A. management of siding with Boeing and dismissing its own experts.

The New York Times