Stipa Caproni Flying Barrel (take off footage only)

The principle of ducted fans is well understood now. They require a duct with correct tapering at each end and a low drag but powerful engine at its core. Multiplebladed propellers, or a fan as on a modern highbypass turbofan are needed for efficiency. Placing a Tiger Moth engine inside a fat tube doesn t cut it. An Italian government engineer, Luigi Stipa, convinced the Caproni Company to build an aircraft to test his theory that a tubular fuselage gave significant extra thrust to a conventional engine a