Abstract: An invention is disclosed for optically determining the position of an object in space, using a single lens for triangulation, wherein an indexing light beam is projected to a lens on one side nonparallel to the optical axis of the lens. The lens focuses the indexing light beam at a known point on the other side of the lens at or near which reflection occurs by the object. Reflected light is captured by the lens and focused toward a photodetector which generates a signal indicating whether reflection occurred at the known point, thus indicating whether the object is present at the known point. If laser light is used, provision is made for, in effect, positioning the laser light source on the optical axis to reduce the effects of laser pointing instabilities. The invention can be used to measure the radii of rotating gas turbine engine rotors.

Abstract: A method of fabricating sheet metal panels and the article produced thereby. According to one form, the method of fabrication includes the steps of providing a panel of sheet metal, perforating the panel to provide a plurality of holes, forming the panel into a preselected curve about a longitudinal centerline, forming the leading edge portion of the panel into a front flange, forming a shoulder in the panel centered on the holes and extending perpendicularly from a surface thereof, bending an outer portion of the shoulder into a lip, and bonding the portions of the panel comprising the shoulder and lip.

Abstract: A signal quantizer is disclosed which compares an input signal with a plurality of predetermined adjustable thresholds, associates with each threshold a potential output signal of predetermined adjustable magnitude, identifies the largest threshold exceeded by the input signal, and produces as an output signal a signal representative of the potential output signal associated with the threshold identified.

Abstract: A ceramic core for use in the casting of a hollow turbine blade comprising at least one passage core portion with first and second opposite surfaces. A plurality of first grooves are disposed on the first surface at a first angle with respect to the centerline of the first surface. A plurality of second grooves are disposed on the second surface at a second angle with respect to the centerline of the second surface. The first angle is less than 90.degree. and the second angle is greater than 90.degree..

Abstract: An improved counterrotating power turbine is disclosed. The power turbine includes a support having an annular axial cross-section and forward and aft portions. The forward portion of the support has a diameter greater than the diameter of the aft portion. Also included are a first rotor and a second rotor. The first rotor is supported on the first portion of the support by first bearing means and extends to the aft portion forming a first interface therewith. The second rotor is supported on the first rotor by second bearing means and extends to the aft portion of the support forming a second interface therewith. In this manner, it is possible to have low diameter slip rings at the first and second interfaces while maintaining relative high diameters for the rotor bearing means.

Abstract: A method consisting of a high temperature diffusion treatment, preferably preceded by a hot isostatic pressing treatment, by which the deleterious effects of hard alpha defects may be substantially reduced or eliminated from ingots of titanium or titanium alloys without adversely affecting the subsequent structure and properties of ingots processed by the method and the homogenized, substantially hard alpha and inclusion-free ingots produced thereby.

Abstract: The present invention comprises a method and apparatus for separating foreign objects from airflow channeled to an aircraft engine. An air intake including a foreign object separator is provided. The air intake includes an inlet duct having a bend for defining a pressure side, which inlet duct is effective for channeling airflow to the engine. A separator aperture is disposed in the pressure side of the inlet duct and a receptacle extends from the inlet duct and is in flow communication with the separator aperture. The receptacle includes a turning wall which is substantially arcuate in both a transverse plane and a longitudinal plane, and is substantially closed for preventing the flow of airflow therethrough while being effective for receiving and capturing foreign objects which enter the inlet duct and pass through the separator aperture.

Abstract: A combustion chamber for use in gas turbine engines is provided with a liner formed of a high temperature material. The liner includes a plurality of panels of the material mounted by means of a slideable friction mounting arrangement upon a high strength structural frame. As a result of this mounting arrangement, the liner is substantially isolated from structural forces associated with the combustion chamber, while the frame is substantially isolated from thermal stresses associated with the liner. Means are provided for positioning and securing individual liner panels in the circumferential, axial, and radial directions with respect to the frame as well as circumferentially with respect to other liner panels. The individual liner panels may be easily removed for repair or replacement without disassembling the frame and associated components. For the purpose of cooling, a cooling fluid is passed into a plenum to cool the radially outward side of the panels by convection.

Abstract: The present invention relates to the manufacture of ionization detectors used in X-ray tomographic imaging. One form of the invention discusses a method of manufacturing an array of ionization detectors which reduces spurious electric currents in the detectors when the detector spacing is in the 1.5 mil range. Also discussed is a method of manufacture of a chamber for containing an ionizable gas such as xenon, and of sealing the detector array at its point of entry into the chamber in order to prevent the escape of xenon.

Abstract: The present invention relates to detectors used in X-ray tomographic imaging. The invention describes a xenon ionization detector having individual detector elements spaced 1.5 mil apart, thus providing high resolution. In one embodiment, a procedure is described for reducing a spurious electric current which was found to arise when such narrow spacings were used.

Abstract: An analyzer for determining the frequency of short bursts of radiation is disclosed. An input signal burst is fed to groups of filters and the filter in each group producing the largest output signal is identified. The frequency response characteristics of the filters identified, as well as the magnitudes of their output signals, are utilized in computation of the frequency of the input signal burst.

Abstract: Compressor discharge pressure (CDP) in a gas turbine engine is sensed. A fall in CDP is interpreted as indicating compressor stall.

Abstract: The invention comprises a system for cooling a component in a gas turbine engine, and, in particular, for cooling an engine electronic control thereof. The cooling system includes a housing for mounting the control having a plurality of heat transfer fins extending outwardly therefrom. The housing is mounted in the engine upstream of a compressor and to a front frame having an aperture through which the fins extend. The front frame defines a flowpath to the compressor and the fins extend into the flowpath without adversely affecting the aerodynamic airflow pattern thereof. In a preferred embodiment, the fins extend substantially only to an inner surface of the front frame, and the housing includes temperature and pressure sensors disposed below root sections of the fins.

Abstract: An air inlet for an aircraft engine is disclosed. The inlet includes a nacelle and a fairing spaced therefrom for defining an inlet duct to the engine. The fairing includes a plurality of inlet apertures in flow communication with ambient air and the nacelle includes at least one outlet aperture which is also in flow communication with ambient air. A plurality of struts extends between the fairing and the nacelle and a plurality of flow channels is provided therein, each extending in flow communication from respective ones of said inlet apertures through said struts and nacelle and to said outlet aperture. During operation, the air inlet receives air, and a portion thereof adjacent to the fairing is channeled through the inlet apertures and flow channels out the outlet aperture into the ambient air flowing over the nacelle to bleed off relatively low pressure recovery air.

Abstract: A method for applying preselected abrasive particles to a cleaned first article surface adjacent a second article surface selected to be substantially free of such abrasive particles includes disposing on the first article surface a first electrically non-conductive tape segment including pores large enough to allow passage of electrodeposition current and electrolyte solution but smaller than the size of abrasive particles to be retained on the first tape segment. The first segment has a porous adhesive layer of relatively low tack level, the adhesive carrying the abrasive particles through a first, relatively weak bond. A second electrically non-conductive tape segment substantially impervious to electrolyte solution and electroplating current and having adhesive on a second segment operating surface is disposed on the second article surface in a manner at least sharing an edge portion with the first segment.

Abstract: A method for applying preselected abrasive particles to an article surface includes providing an electrically non-conductive tape and particle member for use in an electrodeposition type system. The tape includes pores large enough to allow passage of electrodeposition current and electrolyte solution but smaller than the size of abrasive particles to be retained on the tape. The tape has a porous adhesive layer of relatively low tack level, the adhesive carrying the abrasive particles through a first or relatively weak bond. A metallic coating is electrodeposited through pores of the tape and adhesive onto the article surface and about the abrasive particles in contact with such surface. This bonds the abrasive particles to the article surface through a second bond between the metallic coating and the abrasive particle which is stronger than the first, relatively weak bond. Thereafter, the tape and particle member is separated at the first bond from the abrasive particles bonded to the article surface.

Abstract: A means for improving the aerodynamic efficiency of the compressor of an axial flow turbomachine is disclosed. The compressor includes a first airfoil relatively rotatable with respect to a radially disposed surface and a second airfoil, aft of the first airfoil, and fixed with respect to the surface. The surface bounds a flowpath for aft moving fluid. The surface has a circumferentially extending recess radially disposed relative to the airfoils. The recess has a generally aft facing wall, a generally axially directed wall, and a generally forward facing wall. The aft facing wall is oriented so as to provide a barrier to the forward flow of fluid in the clearance between airfoil and surface. The forward facing wall is oriented so as to provide an aerodynamically smooth transition from the recess into the flowpath.

Abstract: The present invention concerns a fuel control for a gas turbine aircraft engine. The control de-riches fuel-air mixture during ground start-ups in order to reduce a temperature within the engine.

Abstract: A turbine arrangement for a gas turbine engine having a sloped gas flowpath through the turbine. The radial axes of the rotor blades and stator vanes in the sloped flowpath are tilted such that the axes are substantially normal to the mean flow streamline of the gases. This arrangement reduces tip losses and thereby increases engine efficiency.