Propulsive ducted fans

Claim 1

A gas turbine power plant; comprising a ducted fan having a rotor with reversible pitch blades, a core engine mounted centrally in the fan duct and coupled to drive the fan, an air intake for the core engine situated in the fan duct downstream of the fan rotor said air intake having an intake lip at its upstream end facing the fan rotor, an annular bypass passage surrounding said core engine and air intake, a fan stator located downstream of the core engine intake in said annular bypass passage which fan stator has stator blades angled oppositely to the blades of the fan rotor in forward pitch setting and curved from a leading edge at an angle tangential to the flow direction of the swirling air leaving the fan rotor to an axially directed trailing edge, inlet guide vanes provided in said core engine iNtake, and flow-correcting blades projecting out from the core engine intake lip which are angled such as to substantially reverse the swirl given by the fan stator to the portion of the initially forward-flowing air that enters the engine intake when the fan rotor is in reverse pitch, while presenting substantially zero incidence angle to the rearward air flow from the fan rotor when the fan is in forward pitch.