The Boeing 747 is an American wide-body commercial jet airliner and cargo aircraft, often referred to by its original nickname, Jumbo Jet. Its distinctive "hump" upper deck along the forward part of the aircraft makes it among the world's most recognizable aircraft, and it was the first wide-body produced. Manufactured by Boeing's Commercial Airplane unit in the United States, the original version of the 747 was envisioned to have 150 percent greater capacity than the Boeing 707, one of the common large commercial aircraft of the 1960s. First flown commercially in 1970, the 747 held the passenger capacity record for 37 years. The four-engine 747 uses a double-deck configuration for part of its length. It is available in passenger, freighter and other versions. Boeing designed the 747's hump-like upper deck to serve as a first class lounge or extra seating, and to allow the aircraft to be easily converted to a cargo carrier by removing seats and installing a front cargo door. Boeing did so because the company expected supersonic airliners (development of which was announced in the early 1960s) to render the 747 and other subsonic airliners obsolete, while the demand for subsonic cargo aircraft would be robust well into the future. The 747 was expected to become obsolete after 400 were sold, but it exceeded critics' expectations with production passing the 1,000 mark in 1993. By April 2017, 1,532 aircraft had been built, with 20 of the 747-8 variants remaining on order. As of January 2017, the 747 has been involved in 60 hull losses, resulting in 3,722 fatalities. The 747-400, the most common passenger version in service, has a high-subsonic cruise speed of Mach 0.85–0.855 (up to 570 mph or 920 km/h) with an intercontinental range of 7,260 nautical miles (8,350 mi or 13,450 km). The 747-400 passenger version can accommodate 416 passengers in a typical three-class layout, 524 passengers in a typical two-class layout, or 660 passengers in a high density one-class configuration. The newest version of the aircraft, the 747-8, is in production and received certification in 2011. Deliveries of the 747-8F freighter version began in October 2011; deliveries of the 747-8I passenger version began in May 2012.