US Patent 9845768 Three stream, variable area, vectorable nozzle

An exhaust nozzle for a gas turbine engine may include a plurality of flap trains in the exhaust stream of the gas turbine engine. The flap trains are operable to selectively control three separate flow paths of gas that traverse the engine. A first stream of is the core airflow. The second stream of air is peeled off of the first stream to form a low pressure fan bypass air stream. The third stream of air traverses along the engine casing and is passed over a flap assembly to aid in cooling. The flaps are operable converge/diverge to control the multiple streams of air.