United Airlines' new Boeing 737 MAX 10 aircraft was spotted with a special livery at a paint shop at Washington's Renton Municipal Airport (RTN) in the United States.

The aircraft in question

The aircraft showcases a distinctive livery with colorful stripes and an engine tagline reading "The future is SAF," and bears the registration N27602. The new livery is promoting United's sustainable aviation fuel (SAF) program, a lower-carbon alternative to regular jet fuel.

The 737 MAX 10 plane has yet to be handed over to United Airlines, as it is currently awaiting type certification from the US Federal Aviation Administration (FAA). It is believed that this is the fourth 737 MAX 10 test aircraft.

In 2022, United placed an order for 100 MAX aircraft and specified that out of the 100 planes, 80 would be the MAX 10 variant. This order was part of the airline's significant purchase, which also encompassed 100 Boeing 787 Dreamliners. According to Boeing orders and deliveries data, United has a total of 445 737 MAX family jets on order.

It is worth noting that the first MAX 10 test aircraft destined for United took to the skies for the first time quite recently. The third test aircraft, bearing United's livery and registered as N27753, joined the thousands of Boeing aircraft in the air for over one hour on November 18, 2022.

MAX 10 certification: what's the latest?

During the maiden flight of the 737 MAX 10, Boeing had initially projected that this latest addition to the MAX family would commence service in 2023. But this anticipated timeline has faced setbacks due to certification and supply chain issues despite. Formal certification will likely occur in 2024.

Even with these challenges, Boeing has amassed many orders for the MAX 10. The company plans to ramp up production from 31 to 50 jets per month over the next several years. There are currently three assembly lines at the plant in Renton and Boeing plans to add a fourth MAX assembly line at its facility in Everett, Washington.

Photo: Tom Boon/Simple Flying

In May 2023, Ryanair, Boeing's largest customer outside the US, announced an order for up to 300 737 MAX 10s - 150 firm orders and an option to purchase another 150 for delivery between 2027 and 2033. This follows last year's announcement from Delta Air Lines for an order of 100 MAX 10s with an option to purchase 30 more.

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