The MAX 7, the smallest single-aisle jet, gained approval in August

The FAA’s October 20 clearance gives Boeing the certification needed to begin delivering the 737 MAX 10 to customers. A market ticker accompanying The Wall Street Journal’s report showed Boeing shares, BA, down 0.50%.

The clearance follows the FAA’s August approval of the MAX 7, the smallest version of the single-aisle jet. It also allows Boeing to deliver all four variants of the single-aisle MAX family to customers.

The long-awaited MAX 10 certification was briefly delayed by a new software glitch. The FAA determined that the issue was not a safety issue.

“After extensive safety reviews—including thousands of hours of test flights—the team at the FAA is ready to approve this critical aircraft for sale,” Transportation Secretary Sean Duffy said in a statement. FAA Administrator Bryan Bedford said Boeing would continue to be held to the highest safety standards.

Boeing had planned to start delivering the MAX 10 and MAX 7 years ago. Two deadly crashes involving another 737 model led to delays and new safety-approval requirements before the jets could begin flying passengers.

The earlier MAX crashes in 2018 and 2019 followed bad angle-of-attack data that triggered a faulty flight-control system and pushed the planes into fatal nosedives. The crashes took 346 lives. Boeing later added safeguards to that system.

The MAX 10 will come with a new safety feature that will eventually be added to other 737 MAX models. The enhanced angle-of-attack system calculates the angle of the plane’s nose versus sensor readings on the aircraft.

Boeing 737s have historically had only two angle-of-attack sensors. If one supplied bad data, the flight computers had no third reading with which to cross-check it and ensure accuracy. Boeing said the new system would reduce the possibility of erroneous data and potentially ease pilots’ workload.

Orders for Boeing’s workhorse aircraft have climbed in recent months. U.S. carriers such as Delta Air Lines, United Airlines and American Airlines are among the expected MAX 10 operators, while Southwest Airlines has placed orders for the MAX 7, the smallest version of the single-aisle jet.

The MAX 10 stretches 143 feet, 8 inches and can hold a maximum of 230 seats, according to Boeing. The model is 27 feet longer and has 58 more seats than the MAX 7.