The Airbus A350-900ULR, the ultra-long-range aircraft due to enter service with Singapore Airlines in the second half of 2018, is in the air and on its way to delivering the world’s longest non-stop flight. Powered by Rolls-Royce Trent XWB engines, the aircraft took a short test flight to certify changes from the A350-900 that will extend its range to 9700 nautical miles and allow it to fly more than 20 hours non-stop. These include a modified fuel system that increases fuel carrying capacity by 24,000 litres (6340 US gallons) without the need for additional fuel tanks as well aerodynamic improvements such as extended winglets. Singapore will use the plane to operate non-stop flights to US destinations such as New York and Los Angeles and has ordered seven of the aircraft. The Singapore-New York service will be the world’s longest commercial service, taking over from Doha-Auckland. The aircraft has a maximum take-off weight of 280 tonnes is a competitor to the Boeing 777-8X, which is expected to have a range of at least 8700nm and a passenger capacity of 350-375 passengers when it enters service in 2022. Australian carrier Qantas is examining both aircraft  as part of its ambitious “Project Sunrise” proposals for non-stop flights on ultra-long-haul routes such as Sydney-London and Sydney-New York. Both sides are confident their aircraft can achieve the mission and Boeing has said it is looking at modifications to the B777-8X to meet the demanding Qantas specifications. READ: Boeing confident of winning Qantas ultra-long-range challenge. The A350 family’s design, carbon fibre construction and gracefully aerodynamic wings allow it operate with a 25 percent reduction in fuel burn compared to older, equivalent aircraft. At the end of March, Airbus had recorded 854 firm orders for the A350 from 45 customers worldwide with Singapore Airlines one of the biggest. Singapore has ordered 67 A350-900s, including the seven ULR variants, and has taken delivery of 21.