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. Multiple-bladed propellers, or a fan as on a modern high-bypass 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