The airplane that many called “the flying barrel” is also widely considered the ugliest plane ever built. However, [Dark Skies] in the video you can see below argues that the Stipa-Caproni was the direct predecessor of the turbofan engine. Either way, it is an interesting and unique part of aviation history.
The plane was built in the days when inventors were experimenting with many different ways to improve aircraft utility and performance. In this case, the inventor built an “intubated propellor” which used a prop to draw air through a venturi tube in an effort to improve engine efficiency. The 570kg vehicle had a wingspan of just over 14 meters and was a bit more than 6 meters long. It could reach about 72 knots and climb to over 3 km.
Caproni was known for making odd planes, including one with nine wings. We couldn’t help but think that the Stipa-Caproni looks like something you’d see in a cartoon, perhaps flown by an animal character. It had both positive and negative features.
The plane was quiet and stable. But it was difficult to take off and land and suffered from drag problems. While there was great interest in the design, but no more planes using the principles in the aircraft were built. However, the Kort nozzle, is a very similar idea used in some maritime applications. Stipa also believed that turbofan jet engines were stolen from his invention, a position that isn’t totally far-fetched.
We’d love to see an RC version of the plane with modern flight controls.