The Airbus A350 is a long-range, wide-body twin-engine jet airliner developed and produced by Airbus. The first A350 design proposed by Airbus in 2004, in response to the Boeing 787 Dreamliner, would have been a development of the A330 with composite wings and new engines. As market support was inadequate, in 2006, Airbus switched to a clean-sheet "XWB" (eXtra Wide Body) design, powered by two Rolls-Royce Trent XWB turbofan engines.
The proposed A350 was a new design, including a wider fuselage cross-section, allowing seating arrangements ranging from an eight-abreast low-density premium economy layout to a ten-abreast high-density seating configuration for a maximum seating capacity of 440–475 depending on variant. The A330 and previous iterations of the A350 would only be able to accommodate a maximum of eight seats per row. The 787 is typically configured for nine seats per row. The 777 accommodates nine or ten seats per row, with more than half of recent 777s being configured in a ten-abreast layout that will come standard on the 777X. The A350 cabin is 12.7 cm (5.0 in) wider at the eye level of a seated passenger than the 787's cabin, and 28 cm (11 in) narrower than the Boeing 777's cabin (see the Wide-body aircraft comparison of cabin widths and seating). All A350 passenger models have a range of at least 8,000 nmi (14,816 km). The redesigned composite fuselage allows for higher cabin pressure and humidity, and lower maintenance costs.