The 1930s were a period of incredible aviation with many eye-catching and unconventional designs. One of the most remarkable was the Italian Stipa-Caproni – a tubular fuselage aircraft with a piston engine in the middle. Some have regarded the Stipa-Caproni as a sort of proto-jet engine. The Stipa-Caproni was the product of the aeronautical engineer Luigi Stipi and the plane manufacturer Caproni. At the start of WWII, Italy had some of the world’s leading military aircraft, but these are now mostly forgotten.