The Federal Aviation Administration (FAA) on Friday announced a $3.1 million fine against Boeing Co., citing a series of safety violations uncovered between late 2023 and early 2024 at Boeing’s Renton, Washington, facility and Spirit AeroSystems’ plant in Wichita, Kansas.

According to the FAA, the violations included “hundreds of quality system failures” and interference with safety officials’ independence. Among the findings, Boeing allegedly:

Presented two unairworthy aircraft to regulators for airworthiness certification.

Pressured a quality inspector to sign off on a jet that failed to meet standards to meet delivery deadlines.

The enforcement action comes in the wake of the Alaska Airlines 737 Max door plug blowout in January 2024, a near-catastrophe that triggered a production cap, intensified federal scrutiny, and led to the resignation of then-CEO Dave Calhoun.

Boeing has 30 days to respond to the FAA’s penalty letters, which outline the violations and proposed fines.

In a statement, the company said it would “continue to work on strengthening our safety culture and improving first-time quality and accountability across our operations.”

Current CEO Kelly Ortberg, who took over last year, has focused on stabilizing production and improving factory quality.

Boeing is producing about 38 aircraft per month and plans to increase that rate to 42 by the end of the year, Ortberg said Thursday.