Propfan

Uncommon card · No. 178196

A propfan, also called a propjet, an open rotor engine, or an open fan engine, is an aircraft engine combining features of turbofans and turboprops. It uses advanced, curved propeller blades without a duct. Propfans first started prototype testing in the 1970s, aiming to combine the speed capability of turbofans with the fuel efficiency of turboprops, especially at high subsonic speeds. However, they have never proceeded beyond testing, never going into commercial use. Over the decades, different efforts to perfect the concept have used names like "open rotor" and "ultra-high-bypass (UHB) turbofan".

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