Abstract: In one aspect, the present invention provides a method for amplifying a signal including generating an input signal and amplifying the input signal utilizing a chopper-stabilized, silicon carbide NMOS depletion mode operational amplifier to produce an amplified output signal.

Abstract: A fuel control system for a gas turbine engine includes logic that is used to facilitate enhanced compressor stall margin when the engine is operating in potential icing conditions is described. The fuel control system is coupled to at least one fuel regulator within the engine, and receives input from a plurality of sensors coupled to the engine. More specifically, the system receives input from environmental sensors, as well as inputs representing compressor inlet temperature, compressor discharge pressure, and corrected core engine speed. Furthermore, the fuel control system also receives input from the other engine fuel regulators.

Abstract: A method facilitates replacing a portion of a gas turbine engine combustor. The combustor includes a combustor liner and a wire-wrapped cowl assembly that includes an inner cowl and an outer cowl. The method comprises cutting through the wire-wrapped cowl assembly upstream from fastener openings used to couple the inner and outer cowls to the combustor liner, removing a portion of the cowl assembly from the combustor, and coupling a replacement cowl to the portion of the existing cowl assembly that is downstream from the cut, wherein the replacement cowl includes an inner annular portion, an outer annular portion, and a plurality of circumferentially-spaced radial ligaments extending therebetween.

Abstract: A method enables a rotor assembly for a gas turbine engine to be fabricated. The method includes forming a blade including an airfoil extending from an integral dovetail used to mount the blade within the rotor assembly, and extending a projection from at least a portion of the blade, such that the stresses induced within at least a portion of the blade are facilitated to be maintained below a predetermined failure threshold for the blade to facilitate preventing failure of the blade.

Abstract: A method enables a variable vane assembly for a gas turbine engine to be coupled to an engine casing. The variable vane assembly includes a bushing assembly and at least one variable vane that includes a platform and a vane stem. The method comprises coupling a first bushing to the engine casing in a press fit, coupling a second bushing to the variable vane, and coupling the variable vane to the engine casing such that at least a portion of the first bushing is between the engine casing and the second bushing, and such that at least a portion of the second bushing is between the first bushing and the vane stem.

Abstract: A method enables a structural cover for a gas turbine engine to be manufactured. The method includes forming a torroidial body including an integrally-formed windage cover portion and a seal flange portion, and forming a plurality offastener openings extending from a forward side of the torroidial body to an aft side of the torroidial body, such that when installed in the gas turbine engine, the windage cover portion facilitates shielding the fastener openings from a gas flow path.

Abstract: A method enables a gas turbine engine multi-domed combustor including an outer liner and an inner liner that define a combustion chamber therebetween to be assembled. The method comprises coupling a first dome including a heat shield that includes an annular endbody that extends a first distance axially from the heat shield to the combustor outer liner, and coupling a second dome including a heat shield that includes an annular endbody that extends a second distance axially from the heat shield to the first dome, such that the second dome is radially aligned with respect to the first dome, and wherein the second dome second distance is less than the first dome first distance.

Abstract: A stiffener system includes a stiffener and a fastener means. The stiffener includes an extruded body that includes a plurality of projections. The stiffener couples to the apparatus to facilitate increasing a structural integrity of the apparatus. The fastener means secures the stiffener to the apparatus.

Abstract: A method for acquiring a plurality of images of an object of interest using a tomosynthesis imaging system. The method includes determining a thickness of an object of interest, and adjusting at least one parameter of an image acquisition process based on the determined thickness.

Abstract: A method for assembling a flap system for a gas turbine engine exhaust nozzle including a plurality of backbone assemblies facilitates extending a useful life of the exhaust nozzle. The method includes providing a flap basesheet having a width defined between a pair of side edges that are coupled together by a leading edge and a trailing edge, and including at least one stiffener that extends between the basesheet side edges and includes an intermediate portion that has a width that is smaller than that of the basesheet and is at least one of bonded to and formed integrally with the basesheet, and coupling the basesheet to the gas turbine engine with a backbone assembly.

Abstract: A method for fabricating a nozzle for a gas turbine engine facilitates extending a useful life of the nozzles. The nozzle includes an airfoil. The method includes forming the airfoil to include a suction side and a pressure side connected at a leading edge and a trailing edge such that a cooling cavity and a cooling circuit are defined within the airfoil, wherein the suction side and the pressure side extend radially between a tip and a root. The method also includes forming a plurality of cooling slots within the airfoil that extend from the cooling circuit towards the airfoil trailing edge, and forming a control vane within the cooling circuit to facilitate maintaining a substantially constant cooling effectiveness within the cooling circuit.

Abstract: A method enables a gas turbine engine positioned within a module to be operated. The engine includes an inlet and an exhaust, and the module includes an inlet area, an exhaust area, and an engine area extending therebetween and housing the engine. The exhaust area includes an exhaust duct and an outlet. The engine is operated such that inlet air is routed through the module inlet and into the engine inlet, wherein exhaust gases are discharged through the module exhaust duct and substantially perpendicularly from the gas turbine engine. The exhaust gases are discharged from the module outlet in a direction that is at least ninety degrees offset from exhaust gases flowing within the exhaust duct. Cooling fluid is discharged from the module engine area through a cooling system exhaust, such that the discharged fluid flows through the cooling system exhaust and around the module exhaust area.

Abstract: A method enables a gas turbine engine variable bypass valve system to be assembled. The method comprises positioning a unison ring circumferentially within the gas turbine engine such that the unison ring is radially outward from a structural frame, coupling at least one bellcrank to the unison ring, such that the unison ring is radially supported only by said at least one bellcrank, and coupling the at least one bellcrank to a bellcrank support that is coupled to the structural frame.

Abstract: A method and apparatus for detecting an impending failure of a process sensor is provided. The method includes determining a sensor output noise component, and comparing the output noise component to a historical sensor output noise signature based on at least one of the range of span of the sensor and the process operating conditions. The apparatus includes a computing device including a processor and a memory communicatively coupled to the processor wherein the processor is programmed to execute a software product code segment that includes a comparator, a data historian, an isolator module, and a limit module. The computing device is configured to detect impending failure of a sensor using an output signal noise component of the sensor and wherein the sensor senses a parameter of a process associated with the computing device.

Abstract: The first-stage buckets have airfoil profiles substantially in accordance with Cartesian coordinate values of X, Y and Z set forth in Table I wherein Z is a perpendicular distance from a plane normal to a radius of the turbine centerline and containing the X and Y values with the Z value commencing at zero in the X, Y plane at the radially innermost aerodynamic section of the airfoil and X and Y are coordinates defining the airfoil profile at each distance Z. The X, Y and Z values may be scaled as a function of the same constant or number to provide a scaled-up or scaled-down airfoil section for the bucket.

Abstract: A method for assembling a flap and seal system for a gas turbine engine exhaust nozzle including a plurality of backbone assemblies facilitates attaching a basesheet to a backbone. The method includes attaching an attachment system including at least one strap to a basesheet, and coupling the basesheet to a backbone using the attachment system strap.

Abstract: A combustor for a gas turbine engine operates with high combustion efficiency, and low nitrous oxide emissions during engine operations. The combustor includes at least one trapped vortex cavity, a fuel delivery system including two fuel circuits, and a fuel spray bar assembly. A pilot fuel circuit supplies fuel to the trapped vortex cavity and a main fuel circuit supplies fuel to the combustor. The fuel spray bar assembly includes a spray bar and a heat shield. The spray bar is sized to fit within the heat shield. The heat shield includes aerodynamically-shaped upstream and downstream sides.