Air Siam was an airline based in Thailand, beginning operations in 1965 as a freight carrier to Hong Kong. With the help from Overseas National Airways (ONA), Air Siam began scheduled service in 1971 with a Douglas DC-8 and scheduling service help from TWA. At the time, Air Siam was also the 2nd largest operator, after Air France, for the new Airbus A300 wide-body jet. For their Bangkok–Los Angeles route, Air Siam leased a B747-100 from Aer Lingus and in 1974 Air Siam purchased a single new Douglas DC-10-30. Air Siam ceased operations in 1976 due to government complications