(AP) – The Federal Aviation Administration on Monday approved the smallest model of Boeing’s Max jetliners for commercial service nearly a decade after the aircraft manufacturer first unveiled the plane.

Certification of the Boeing 737 Max 7 represents a milestone in the company’s work to overcome years of safety, quality and production challenges. The long-delayed Max 7 is part of Boeing’s 737 family of commercial jets, which is the company’s bestseller and has been at the center of its troubles.

The FAA said it cleared the new plane after years of additional testing, design changes and an extensive review of its design and safety systems. The certification was delayed as Boeing addressed technical issues and heightened regulatory scrutiny following two crashes involving the larger Max 8 that killed 346 people in 2018 and 2019.

Since the crashes off the coast of Indonesia and in Ethiopia, the FAA overhauled how it certifies Boeing aircraft. It said its oversight of the company would continue beyond the Max 7’s approval.

Before signing off on the aircraft, the FAA said, it required Boeing to make several safety changes, including updating flight-control software, improving cockpit alerts for pilots and redesigning the engine anti-ice system to prevent overheating.

“Our team of dedicated engineers and test experts worked through challenges, an extended pandemic, and the transition to new certification processes,” said Stephanie Pope, president and CEO of Boeing Commercial Airplanes.

Safety inspectors will remain at Boeing production facilities to monitor manufacturing, including observing the company’s Safety Management System and overall safety culture, the agency said.

The Max 7 is expected to be used primarily on short- and medium-haul routes. Several carriers, including Southwest Airlines, have outstanding orders for the plane.