Abstract: A method for operating a gas turbine engine including a core engine, a fan assembly for pressurizing air, a core stream duct, an inner bypass duct, and an outer bypass duct is provided. The method includes channeling a first portion of air discharged from the fan assembly through the core gas turbine engine, channeling a second portion of the air discharged from the fan assembly through the inner bypass duct such that the second portion of air bypasses the core gas turbine engine, mixing the core gas turbine engine exhaust air and the second portion of air, channeling the mixed air through a core engine nozzle, and channeling a third portion of the air discharged from the fan assembly through a bypass nozzle.