SAS Technical Services, TUI fly Nordic and Priority Aero Maintenance. have large aircraft hangars and maintenance facilities at the airport. SAS Technical Services is headquartered at Arlanda and has hangar facilities suitable for widebody aircraft up to the size of Boeing 747-400s. The first part of the hangar complex was built to handle SAS' fleet of DC-8s. There are a number of positions on each side of the building initially built to handle the type. The hangar space are nowa used mostly for Boeing 737s and A320s. The Boeing 747 hangar was inaugurated at the time when Scandinavian Airlines received their first Boeing 747s in the beginning of the 70s. It is large enough to handle a Boeing 747 and two 737 sized airplanes at the same time. The offices of SAS Technical Services are situated in connection with the hangars. In the early days of the airport these hangars provided heavy maintenance for members of the KSSU group, which included KLM, SAS, Swissair and UTA. A number of other airlines, such as Thai Airways International, also maintained their aircraft in those hangars. Now the main user is Scandinavian Airlines. TUI fly Nordic has a hangar able to handle their largest aircraft, the Boeing 787-9. Priority Aero Maintenance has its facilities in the eastern part of the airport. They provide heavy aircraft maintenance for a number of aircraft including MD-80, a common type to be overhauled by the company.