High Quality Content by WIKIPEDIA articles! Scandinavian Airlines (SAS), previously known as Scandinavian Airlines System, is the national airline of Denmark, Norway and Sweden. Headquartered in Sigtuna outside Stockholm, Sweden, it operates out of three main hubs, Copenhagen Airport, Stockholm-Arlanda Airport and Oslo Airport, Gardermoen. Owned by the eponymous SAS Group, the airline transported 22.9 million passengers to 90 destinations on an average 683 flights daily in 2011. As of 2012, SAS operates 133 aircraft—all jetliners—consisting of 74 Boeing 737, 24 McDonnell Douglas MD-80, 12 Bombardier CRJ900, 12 Airbus A319/A321 and 11 Airbus A330/A340.