by BLOOMBERG

Boeing Co.’s biggest 737 Max model is set to take its initial flight as soon as Friday morning, marking another milestone in the jet family’s comeback from tragedy and a lengthy grounding, according to people briefed on the matter.

The Max 10 will be the first 737 model to take its maiden flight since U.S. regulators cleared the jets to re-enter the market in November. The jetliner isn’t expected to enter commercial service until 2023, providing extra leeway as Boeing works with regulators to certify changes to how the aircraft measures air flow.

European officials demanded that Boeing add so-called synthetic sensors last year as an extra precaution after faulty indicators were linked to two fatal 737 Max crashes that killed 346 people and prompted the flying ban. The technology will be tested on the Max 10 and eventually retrofitted on the rest of the fleet.

Friday’s flight is scheduled for 10 a.m. Seattle time, although the schedule could change depending on weather or other factors, said the people, who asked not to be identified since the plans are confidential. The plane was rolled out in late 2019 and remained in storage as the Chicago-based planemaker worked with regulators to end the broader grounding.

The Max 10 is the final planned Max model, and also the largest of the single-aisle jets. The aircraft can seat as many as 230 travelers in a single-cabin configuration favored by budget carriers and fly 3,300 nautical miles (about 6,000 kilometers) if outfitted with an auxiliary fuel tank.

Boeing borrowed its landing gear design from the wide-body 777 jetliner to accommodate a frame stretched to compete with Airbus SE’s hot-selling A321neo jets. Boeing is also working to certify the smallest Max, the Max 7, as well as its initial 777X jetliner.