Patent attributes
A rocket thruster of this invention includes a nozzle and a valve assembly. The valve subassembly includes a pintle with a head portion, which has a truncated substantially conical surface region facing and concentric with converging and throat regions of the nozzle to provide a variable effective throat area therebetween. The truncated portion of the head portion has an outer edge defining a bleed passageway opening communicating with a primary bleed passage leading through the head portion to a bleed cavity located on an opposite side of the head portion. During activation of a rocket motor to which the rocket thruster is coupled, gases imparting a load on the head portion pass through the primary bleed passage to the opposite side of the head portion for counterbalancing loads acting on the head portion. A thrust control subassembly moves the pintle axially for changing the effective throat area.