USS Langley (CV-1/AV-3) was the United States Navy's first aircraft carrier, converted in 1920 from the collier USS Jupiter , and also the US Navy's first turbo-electric-powered ship. Conversion of another collier was planned but canceled when the Washington Naval Treaty required the cancellation of the partially built Lexington-class battlecruisers Lexington and Saratoga, freeing up their hulls for conversion to the aircraft carriers Lexington and Saratoga. Langley was named after Samuel Langley, an American aviation pioneer. Following another conversion to a seaplane tender, Langley fought in World War II. On 27 February 1942, while ferrying a cargo of USAAF P-40s to Java, she was attacked by nine twin-engine Japanese bombers of the Japanese 21st and 23rd naval air flotillas and so badly damaged that she had to be scuttled by her escorts. She was also the only carrier of her class.

USS Lexington (CV-2), nicknamed "Lady Lex", was the name ship of her class of two aircraft carriers built for the United States Navy during the 1920s. Originally designed as a battlecruiser, she was converted into one of the Navy's first aircraft carriers during construction to comply with the terms of the Washington Naval Treaty of 1922, which essentially terminated all new battleship and battlecruiser construction. The ship entered service in 1928 and was assigned to the Pacific Fleet for her entire career. Lexington and her sister ship, Saratoga, were used to develop and refine carrier tactics in a series of annual exercises before World War II. On more than one occasion these included successfully staged surprise attacks on Pearl Harbor, Hawaii. The ship's turbo-electric propulsion system allowed her to supplement the electrical supply of Tacoma, Washington, during a drought in late 1929 to early 1930. She also delivered medical personnel and relief supplies to Managua, Nicaragua, after an earthquake in 1931.