You’re right, these aren’t WW1 biplanes, although they have been used as such in low-budget movies. They were designed by Lloyd C. Stearman (1898-1975), who was born at Wellsford, Kansas, which is today a mostly abandoned town in Kiowa County, about 120 miles west of Wichita.
He grew up in Harper, another small town fifty miles southwest of Wichita. In 1917 he enrolled at the Kansas State Agricultural College in Manhattan where he studied architecture until he enlisted in the US Navy Reserve Flying Corps in August, 1918. He was sent to the University of Washington for Ground School then to North Island in San Diego where he was training on the Curtis N-9 seaplane when his service was terminated after the armistice. He returned to Kansas at the end of the year, taking employment as a draftsman with an architectural firm in Wichita.
Soon he went to work, also as a draftsman, for the E.M. Laird Co., also in Wichita, which was manufacturing an aircraft called the Swallow. By 1924 he was their chief engineer and had designed several improved versions.
Then in February, 1925 there happened a truly Hollywood moment, when Stearman partnered with fellow aviation legends-to-be Walter Beech and Clyde Cessna to form a new company in Wichita called TravelAir. Their company produced a series of small passenger aircraft, some designed by Stearman and others by Beech. TravelAir was sold to Curtis-Wright in 1930 and Beech moved on to start Beechcraft.
Stearman had already left TravelAir in 1926, going to California, where he built a couple of aircraft of his own design but ran out of cash. In 1927 he was able to get new investors from Wichita on the condition that the company would relocate there. These Stearman aircraft were used for pilot training, carrying airmail and single passengers to remote locations and for aerial spraying. In 1929 his investors took their gains and sold out to the conglomerate United Aircraft and Transportation Corp. (UATC).
The government split up UATC in 1934 and Stearman Aircraft became a subsidiary of Boeing, remaining in Wichita, and starting a long association between Boeing and the city. As for Stearman himself, he had stayed for only a year before becoming disgusted with his cigar-chomping bosses in Connecticut, but in that year he produced the Stearman Model 6, the precursor of the Boeing Model 75, designated by the US Army as the PT-13 and PT-17 “Kaydet” (or by the US Navy as NS-1 and NS-2)
which became the principal primary flight trainer for the US military and 19 other air forces during and after WW2. A total of 10,626 Model 75’s were built and the aircraft endures to the present day primarily as a stunt plane, and is still popularly called ‘the two-hole Stearman’.
Returning to Stearman’s story, he went back to California where he was hired to run the bankrupt Lockheed Aviation. He stayed four years, during which he co-designed the famous Lockheed Model 10 Electra, the aircraft type that Amelia Earhart was flying when she was lost in 1937. After leaving Lockheed he pursued many other opportunities in the California aviation industry and in 1955 he rejoined Lockheed as a designer, retiring in 1968.