The Airbus A380 is a double-deck, wide-body, four-engine jet airliner manufactured by Airbus. It is the world's largest passenger airliner; many airports have upgraded their facilities to accommodate it because of its size. Initially named Airbus A3XX, Airbus designed the aircraft to challenge Boeing's monopoly in the large-aircraft market; the A380 made its first flight on 27 April 2005 and entered commercial service in October 2007 with Singapore Airlines. The A380's upper deck extends along the entire length of the fuselage, with a width equivalent to a wide-body aircraft. This gives the A380-800's cabin 478 square metres of floor space, which is 40% more than the next-largest airliner, the Boeing 747-8, and provides seating for 525 people in a typical three-class configuration or up to 853 people in an all-economy class configuration. The A380-800 has a design range of 15,700 kilometres, sufficient to fly nonstop from Dubai to Los Angeles, and a cruising speed of Mach 0.85. As of December 2013 Airbus has received 304 firm orders and delivered 122 aircraft. Emirates has the most A380s on firm order with 140 as of December 2013.