Methods, apparatus, systems, and articles of manufacture are disclosed for a variable bleed valve assembly. An example variable bleed valve assembly a variable bleed valve (VBV) door corresponding to a bleed port and a first unison ring, the VBV door coupled to the first unison ring, the first unison ring to move in a circumferential direction between a first position and a second position causing the VBV door to move between the first position and the second position.

A sleeve valve includes an inlet port and an outlet port. A sleeve is movable to close flow from the inlet port to the outlet port. The sleeve valve has a sleeve biased to an open position at which it allows flow from the inlet port to the outlet port by a spring. Pressure in a pressure chamber urges the sleeve to a closed position at which it blocks flow from the inlet port to the outlet port. A line pressure conduit communicates the fluid chamber into the pressure chamber. Pressurized air is supplied to the pressure chamber through a selectively closed valve. The selectively closed valve is opened to allow the flow of high pressure air from a pressure source into the pressure chamber to move the sleeve to a closed position. A bleed air system for a gas turbine engine is also disclosed.

A gas turbine engine comprising: a duct extending about an axis, the duct including an outer-duct wall having an interior-duct surface circumscribing an interior of the duct and an exterior-duct surface radially outward of the interior-duct surface relative to the axis, the outer-duct wall defining an offtake opening extending from the interior-duct surface to the exterior-duct surface, the offtake opening in fluid communication between an offtake location inside the duct and outside the duct, and a bleed air offtake assembly including: an air line in fluid communication with inside the duct via the offtake opening, the air line having a first-line end defining a line inlet proximate to the outer-duct wall and a second-line end spaced from the first-line end; a valve located outside the duct and fluidly connected to the air line via the second-line end, and a conduit having a conduit inlet in fluid communication with inside the air line at a resonance location between the first-line end and the second-line end upstream of the valve, and a conduit outlet in fluid communication with inside the duct at a relief location spaced from the offtake location.

A system for use in servicing a machine. The system includes a tubular body including a longitudinal axis, a tip end, a dispensing nozzle defined at the tip end, and an interior channel in flow communication with the dispensing nozzle. The tubular body is configured to be flexible. An actuator is configured to selectively modify an orientation of the tubular body, and a reservoir is in flow communication with the interior channel. The reservoir is configured to supply a maintenance fluid to the tubular body for discharge from the dispensing nozzle.

An aircraft engine, has: a duct having an inlet, an outlet, and a bleed port through a wall of the duct; a bleed conduit stemming from the duct; a first valve connected to the bleed conduit and having an open configuration and a closed configuration; and a second valve connected to the bleed conduit upstream of the first valve and at or proximate the bleed port, the second valve having a second open configuration and a second closed configuration, when in the second closed configuration, the second valve blocking fluid communication between the bleed port and the first valve such that a portion of the bleed conduit between the first valve and the second valve is fluidly isolated from the duct, the second valve being in the second open configuration when the first valve is in the open configuration.

An orifice pack is provided for delivering pressurized air to a compressor bleed valve of a gas turbine engine. The orifice pack has a diffusion chamber in serial flow communication with a tapering passage and a first outlet passage for venting a first portion of the pressurized air from the diffusion chamber. A second outlet passage branches off from the diffusion chamber at an axial location between the inlet and the tapering passage. The second outlet passage is fluidly connected to the compressor bleed valve for directing a second portion of the pressurized air from the diffusion chamber to the compressor bleed valve.

The gas turbine engine can have a pneumatic actuator; an intake device secured to a gas path wall delimiting the gas path, the intake device having a tubular body protruding from the gas path wall into the gas path and an inlet aperture formed in the tubular body, the inlet aperture spaced-apart from the gas path wall and facing downstream relative a flow orientation of the gas path, the intake device having an internal conduit extending from the inlet aperture, along the tubular body, to an outlet across the gas path wall; and a fluid line fluidly connecting the outlet of the intake device to the pneumatic actuator.

A system for use in servicing a machine. The system includes a tubular body including a longitudinal axis, a tip end, a dispensing nozzle defined at the tip end, and an interior channel in flow communication with the dispensing nozzle. The tubular body is configured to be flexible. An actuator is configured to selectively modify an orientation of the tubular body, and a reservoir is in flow communication with the interior channel. The reservoir is configured to supply a maintenance fluid to the tubular body for discharge from the dispensing nozzle.

A sleeve valve includes an inlet port and an outlet port. A sleeve is movable to close flow from the inlet port to the outlet port. The sleeve valve has a sleeve biased to an open position at which it allows flow from the inlet port to the outlet port by a spring. Pressure in a pressure chamber urges the sleeve to a closed position at which it blocks flow from the inlet port to the outlet port. A line pressure conduit communicates the fluid chamber into the pressure chamber. Pressurized air is supplied to the pressure chamber through a selectively closed valve. The selectively closed valve is opened to allow the flow of high pressure air from a pressure source into the pressure chamber to move the sleeve to a closed position. A bleed air system for a gas turbine engine is also disclosed.

A propulsion system for an aircraft includes a rotor and a nacelle fairing that extends around the rotor in relation to an axis. The nacelle fairing includes an upstream portion forming an inlet section of the nacelle fairing as well as a downstream portion, a downstream end of which forms an outlet section of the nacelle fairing. The downstream portion includes radially inner and outer walls, both of which are made of a deformable shape memory material. The wall has independently actuatable piston actuator mechanisms, each actuator mechanism being actuatable independently of the others and being designed to cooperate with means built into an inner surface of the wall to deform the wall in a radial direction in relation to the axis under the effect of a predetermined displacement command.