American Airlines is a major US-based airline headquartered in Fort Worth, Texas, within the Dallas–Fort Worth metroplex. It is the largest airline in the world when measured by fleet size, scheduled passengers carried, and revenue passenger mile. American, together with its regional partners and affiliates, operates an extensive international and domestic network with almost 6,800 flights per day to nearly 350 destinations in more than 50 countries. American Airlines is a founding member of the Oneworld alliance, the third-largest airline alliance in the world. Regional service is operated by independent and subsidiary carriers under the brand name American Eagle. American Airlines and American Eagle operate out of 10 hubs, with Dallas/Fort Worth (DFW) being its largest. The airline handles more than 200 million passengers annually with an average of more than 500,000 passengers daily. As of 2021, the company employs 123,400 staff members. History American Airlines was started in 1930 via a union of more than eighty small airlines. The two organizations from which American Airlines was originated were Robertson Aircraft Corporation and Colonial Air Transport. The former was first created in Missouri in 1921, with both being merged in 1929 into holding company The Aviation Corporation. This, in turn, was made in 1930 into an operating company and rebranded as American Airways. In 1934, when new laws and attrition of mail contracts forced many airlines to reorganize, the corporation redid its routes into a connected system and was renamed American Airlines. Between 1970 and 2000, the company grew into being an international carrier, purchasing Trans World Airlines in 2001. American had a direct role in the development of the DC-3, which resulted from a marathon telephone call from American Airlines CEO C. R. Smith to Douglas Aircraft Company founder Donald Wills Douglas Sr., when Smith persuaded a reluctant Douglas to design a sleeper aircraft based on the DC-2 to replace American's Curtiss Condor II biplanes. (The existing DC-2's cabin was wide, too narrow for side-by-side berths.) Douglas agreed to go ahead with development only after Smith informed him of American's intention to purchase 20 aircraft. The prototype DST (Douglas Sleeper Transport) first flew on December 17, 1935, (the 32nd anniversary of the Wright Brothers' flight at Kitty Hawk). Its cabin was wide, and a version with 21 seats instead of the 14–16 sleeping berths of the DST was given the designation DC-3. There was no prototype DC-3; the first