In the late 1950s, the US Air Force funded a secret project to develop a flying saucer. Avro Canada engineer John "Jack" Frost—the main mind behind the Avrocar—was deep into the "Coandă effect," a phenomenon in which fluid (including air) coming from an orifice stays close to the surrounding flat or curved surface, creating an area of lower pressure. For the VZ-9, the idea was that the Coandă effect would redirect the air under the vehicle to provide lift. Unfortunately, it didn't make the grade as a high-speed combat aircraft so the US Army picked up the project, hoping to be the basis of a new kind of helicopter. As evidenced by the video below, that didn't quite work out either. The project was cancelled in 1961…. or was it?!