It sits on the north side of Paine Field and includes the largest building in the world by volume at over 472 million cubic feet (13,400,000 m3), which covers 98.3 acres (39.8 ha).[1] The entire complex covers approximately 1,000 acres (400 ha) and spans both sides of State Route 526 (named the Boeing Freeway).[11][12] The main assembly building, immediately north of the Boeing Freeway, covers 98.3 acres (398,000 m2) and is organized into six production lines that are separated by walls, offices, and other spaces.[4][23] An urban legend states that clouds used to form inside the main building due to its size prior to the installation of upgraded ventilation systems.[27] The south side includes a set of three paint hangars,[27] a delivery center with conference rooms,[28] and parking spaces for airplanes.[29] The flight line area connects to the main runway at Paine Field, which is 9,010 feet (2,750 m) long and is the only one at the airport that can accommodate jetliners.[37][40] On June 17, 1966, the company announced that it had selected a site adjacent to Paine Field as the future home of its Boeing 747 assembly plant.[53] To accommodate the Dreamlifter, a converted 747-400 which delivered 787 sections to the plant, a base was constructed on the western edge of Paine Field's runway.[56] The factory was shut down for three weeks until workers were able to return with mandatory face masks, social distancing, and staggered start times to reduce potential exposure.First introduced in 1979 to complement the larger 747, the aircraft was capable of carrying 218 passengers in a typical three-class configuration over a range of 5,990 nautical miles (6,890 mi; 11,090 km) and a cruising speed of Mach 0.80 (530 mph, 851 km/h, 470 kn).[68][69] Undertaking drastic cost-cutting measures in the wake of the COVID-19 pandemic and its resulting impact on aviation, Boeing announced in July 2020 that it would consider consolidating all of its 787 assembly in a single location; the company chose to move all production to South Carolina on October 1, causing backlash from the Washington state government.[70][71] The move was completed in February 2021; it was cemented with Boeing's agreement to transfer its lease of the Dreamlifter Operations Center to package courier FedEx in April 2021.