An engine assembly includes a nacelle configured to at least partially surround an engine and a thrust reverser coupled to the nacelle. The thrust reverser includes: a thrust-reversing element movable relative to the nacelle between a stowed position and a deployed position; a hydraulic actuator operably coupled to move the thrust-reversing element; and a fluid control system configured to operate the hydraulic actuator. The fluid control system includes: a directional control unit including a directional control valve operable to selectively route fluid between a pressurized fluid source, the actuator, and a fluid return reservoir; one or more bypass fluid lines providing fluid communication between the actuator and the fluid return reservoir independent of the directional control valve; and a flow limiter residing between the pressurized fluid source and the directional control valve, the flow limiter configured to inhibit a pressure draw by the actuator from surpassing a predetermined threshold.

A propulsion system coupled to a vehicle. The system includes a diffusing structure and a conduit portion configured to introduce to the diffusing structure through a passage a primary fluid produced by the vehicle. The passage is defined by a wall, and the diffusing structure comprises a terminal end configured to provide egress from the system for the introduced primary fluid. A constricting element is disposed adjacent the wall. An actuating apparatus is coupled to the constricting element and is configured to urge the constricting element toward the wall, thereby reducing the cross-sectional area of the passage.