The prototype of the Mong Sport biplane was built and first flown by Ralph E. Mong, Jr., of Tulsa, Oklahoma, in 1953. It was a small, one-place, open-cockpit aircraft designed for sale as a home-build kit. The original ribs were made from silver-soldered welding rods! Commenting on the diminuitive dimensions of the Sport, Mong (who is 5 foot 2 1/2 inches tall) said "If I'm gonna build an airplane, by golly it's gonna fit!"

Mong sold around 400 sets of plans for the Sport and at least 200 were eventually built in the United States and Canada. The Sport prototype was donated to the Experimental Aircraft Association in Oshkosh, Wisconsin, in 1986.

This aircraft, N4253J (airframe S/N 1937), was assembled by Robert McAuley and his students in the Aviation Department of Lewis University in Romeoville, Illinois. Well over 1,100 hours of labor went into the project before "first flight" on 29 June 1993. Over 60 flight hours were accumulated on the airframe by the time it was sold in 1996 to Marcellus F. Foose of Blue Island, Illinois. The plane is located in the museum's new exhibit, Barnstormers, Wing-walkers, and Entrepreneurs: 150 Years of Aviation section.