The Travel Air 2000/3000/4000 were open-cockpit biplane aircraft produced in the United States in the late 1920s by the Travel Air Manufacturing Company. During the period from 1924–1929, Travel Air produced more aircraft than any other American manufacturer, including over 1,000 biplanes. While an exact number is almost impossible to ascertain due to the number of conversions and rebuilds, some estimates for Travel Air as a whole range from 1,200 to nearly 2,000 aircraft.

A biplane is a fixed-wing aircraft with two main wings stacked one above the other. The first powered, controlled aeroplane to fly, the Wright Flyer, used a biplane wing arrangement, as did many aircraft in the early years of aviation. While a biplane wing structure has a structural advantage over a monoplane, it produces more drag than a monoplane wing. Improved structural techniques, better materials and higher speeds made the biplane configuration obsolete for most purposes by the late 1930s.