Boeing is performing the final taxi tests of its first 737 MAX 10 aircraft, the fourth version of the MAX series.

Pictures posted on Twitter by Katie Bailey show N27751 moving about on taxiways and performing taxiing tests.

For the moment, 20 customers have ordered 550 aircraft of this model, first launched in 2017 at the Paris Air Show. Boeing 737 MAX can fly 6,110 kilometers and carry up to 230 passengers. United Airlines ordered 100 MAX10s in addition to its MAX9.

“Airlines wanted bigger and better options in the larger single-aisle segment with the operational benefits of the 737 MAX family.” Boeing said when it launched the MAX10.

“With the addition of the 737 MAX 10, customers will be the most flexible on the market and will be able to offer them the range, fuel efficiency and outstanding reliability that are widely known in the 737 MAX family.”