Boeing BA-N announced plans to acquire Spirit AeroSystems for $4.7 billion in an all-stock transaction for the manufacturing firm, which already was part of the aerospace company’s manufacturing chain.

Boeing, located in Arlington, Virginia, announced the purchase in a statement late Sunday.

The acquisition’s equity value of $4.7 billion is $37.25 per share, while the total value of the deal is around $8.3 billion, which includes Spirit’s last reported net debt, the aerospace company said.

Spirit, located in Wichita, Kansas, manufactures key parts for Boeing aircraft. Spirit also announced the acquisition on its website and social media.

“We believe this deal is in the best interest of the flying public, our airline customers, the employees of Spirit and Boeing, our shareholders and the country more broadly,” Boeing President and CEO Dave Calhoun said in the statement.

Boeing previously owned Spirit and the aerospace company said bringing the supplier back into the Boeing fold would improve plane quality and safety, which has come under increasing scrutiny by regulators, Congress and airlines.

“By reintegrating Spirit, we can fully align our commercial production systems, including our Safety and Quality Management Systems, and our work force to the same priorities, incentives and outcomes – centred on safety and quality,” Calhoun said.

The purchase of Spirit would reverse a long-time Boeing strategy of outsourcing key work on its passenger planes. That approach has been criticized as problems at Spirit disrupted production and delivery of popular Boeing jetliners including 737s and 787s.

Concerns about safety came to a head after the Jan. 5 blowout of a panel on an Alaska 737 Max 9 at 16,000 feet (4,876 meters) over Oregon. The Federal Aviation Administration soon after announced increased oversight of Boeing and Spirit.

The Justice Department said in a May court filing that Boeing violated terms of a 2021 settlement allowing the company to avoid prosecution for actions leading up to two deadly crashes involving the company’s 737 Max jetliners more than five years ago.

The Justice Department is pushing Boeing to plead guilty to criminal fraud in connection with two deadly plane crashes involving its 737 Max jetliners, according to several people who heard federal prosecutors detail a proposed offer Sunday.

Boeing has until the end of the week to accept or reject the offer, which includes the giant aerospace company agreeing to an independent monitor who would oversee its compliance with anti-fraud laws, they said.