HIGH BYPASS RATIO ENGINE BYPASS DUCT NOZZLE WITH CONTROLLED NOZZLE AREA

A nacelle assembly of a gas turbine engine (20) includes an annular structure defining a central axis, and having a radially inward surface (110) and a radially outward surface, the radially inward surface (110) at least partially defining a bypass duct (106). An aft portion of the radially inward surface (156) at least partially defines an axially extending convergent-divergent exit nozzle (100). A secondary nozzle flap (134) is radially spaced from the aft portion of the radially inward surface (156). The secondary nozzle flap (134) and the aft portion of the radially inward surface (156) define a secondary bypass duct (124) therebetween. The secondary nozzle flap (134) is operably connected to the annular structure such that the secondary nozzle flap (134) is selectably movable relative to the aft portion of the radially inward surface (156), thereby changing a cross-sectional area (166) of a secondary bypass duct exit.