Trans World Airlines (TWA) was a trunk carrier, a scheduled airline in the United States that operated from 1930 until it was acquired by American Airlines in 2001. It was formed as Transcontinental & Western Air to operate a route from New York City to Los Angeles via St. Louis, Kansas City, and other stops, with Ford Trimotors. With American, United, and Eastern, it was one of the "Big Four" domestic airlines in the United States formed by the Spoils Conference of 1930.
Howard Hughes acquired control of TWA in 1939, and after World War II led the expansion of the airline to serve Europe, the Middle East, and Asia, making TWA a second unofficial flag carrier of the United States after Pan Am. Hughes gave up control in the 1960s, and the new management of TWA acquired Hilton International and Century 21 in an attempt to diversify the company's business.