Static performance of a multiaxis thrust vectoring cruciform nozzle

A multiaxis thrust vectoring nozzle designed to have equal flow turning capability in pitch and yaw is investigated, and methods for obtaining large multiaxis thrust vector angles without physical vectoring flap interference are studied. These methods include restricting the pitch flaps from the path of the yaw flaps, and shifting the flow path at the throat off the nozzle centerline in order to permit larger pitch flap deflections without interfering with operation of the yaw flaps. The results obtained show that unvectored performance of the cruciform nozzle is only slightly lower (0.5 to 1.0 percent) than that of previously tested axisymmetric and nonaxisymmetric nozzles, despite the complex internal geometry. The shifted-throat nozzle design has larger thrust vector angles at the nozzle pressure ratio of peak resultant thrust efficiency, but has 1 to 2 percent lower peak thrust performance than the restricted-flap nozzle design.