1. Field of the Invention
This invention relates generally to axisymmetric variable throat thrust vectoring nozzles and, more particularly, to the support apparatus of the vectoring ring that is used to pivot the nozzle flaps that vector the nozzle exhaust flow.
2. Description of Related Art
For military aircraft applications, there exists a need to increase the maneuverability of the aircraft both for air to air combat missions and complicated ground attack missions. Aircraft designers seek to replace or augment the use of conventional aerodynamic surfaces such as flaps and ailerons with vectorable nozzles which turn or vector the exhaust flow and thrust of the gas turbine engine powering the aircraft. Hauer in U.S. Pat. No. 4,994,660, herein incorporated by reference, discloses an axisymmetric vectoring exhaust nozzle that provides a means for vectoring the thrust of an axisymmetric convergent/divergent nozzle by universally pivoting the divergent flaps of the nozzle in an asymmetric fashion or in other words pivoting the divergent flaps in radial and tangential directions with respect to the unvectored nozzle centerline. The flaps are pivoted by a vectoring ring which can be axially translated and gimballed or tilted about its horizontal and vertical axis (essentially have its attitude adjusted) through a limited range. Previously, two dimensional nozzles have used vectored thrust means that employ relatively flat flaps to direct the pitch or yaw direction of the engine's thrust.
Vectored thrust produces tangential and radial loads referred to as side loads that are transmitted from the flaps by various load paths back to the engine casing through the actuators. These tremendous loads require heavy actuators to absorb the loads and particularly the bending moments exerted on the actuator shafts by thrust vectoring.
It is therefore one object of the present invention to provide a means to minimize or eliminate the side loads transferred by the nozzle to the actuators. It is another object of the present invention to reduce or eliminate the bending moments that the actuators would be subject to due to the radial loads. Another object is to minimize the size and weight of the nozzle actuators and hydraulic system used to power the actuators.
These objects and other features and advantages will become more readily apparent in the following description when taken in conjunction with the appended drawings.