Abstract: The present invention relates to an endoscope for the examination of the interiors of lightening holes in gas turbine engine blades. A light beam is projected toward a beam splitter and reflected by the beam splitter into the lightening hole for illumination of the hole. An observation lens system is arranged to allow an observer to view the illuminated hole through the beam splitter.

Abstract: In one form of the present invention, boundary layer air is diverted from a probe in an aircraft and freestream air is induced to impinge upon the probe.

Abstract: In the present invention, the temperatures of cooling passages in a gas turbine engine blade are changed, as by forcing a heated gas through them. The infrared signatures of the channels are measured during the initial temperature transient of the channels and the signatures are compared with a reference. The reference may be the signature of other channels on the same blade.

Abstract: In the invention, a noncylindrical sleeve deforms when a cylindrical nut is threaded into it. The deformation inhibits rotation of the nut because the sleeve is restrained against rotation.

Abstract: An invention is disclosed which supports an eddy curent probe at a predetermined distance from a surface to be scanned. In another embodiment, the probe is scanned by rotation about an axis and along an arc of predetermined length and position.

Abstract: In the present invention, a discrete region of the TBC is heated, as by applying a controlled quantity of laser energy onto the region for a time interval. Then, the radiant thermal energy of a region outside the laser strike region is measured at a predetermined time following the termination of the laser pulse. The intensity of this measured radiant energy is then compared with the radiant intensities which have been experimentally obtained from known thickness specimens and the thickness is inferred therefrom.

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 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: 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 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: An invention is disclosed for positioning an object wherein three point supports provide three contact points which define a first plane. Three additional point supports provide three additional contact points which are not coplanar with the first plane and which define a second plane. The first and second planes are nonperpendicular. The point supports accurately and repeatably position the object for optical measurement of a dimension of the object. The invention can be used in connection with the quality control testing of weldments which attach blade tips to gas turbine engine blades.

Abstract: In the present invention, fuel flow in an aircraft is modulated automatically in order to maintain a preselected altitude.

Abstract: In one form of the present invention, the thrust of a gas turbine engine is inferred. If a droop in thrust is predicted, components of the engine are modulated in response to restore thrust.

Abstract: The present invention utilizes a wire wool slug packed inside a helical coil of an aircraft engine sensor in order to reduce vibration damage to the coil.

Abstract: A multiple-impingement cooled structure, such as for use as a turbine shroud assembly. The structure includes a plurality of baffles which define with an element to be cooled, such as a shroud, a plurality of cavities. Impingement cooling air is directed through holes in one of the baffles to impinge upon only the portion of the shroud in a first cavity. That cooling air is then directed to impinge again upon the portion of the shroud in a second cavity.

Abstract: The present invention includes a pair of cantilevered probes. A first fastening means is fastened to a first of the probes and is loosely journaled about the second probe. A second fastening means is fastened to the second probe and is loosely journaled about the first probe. The invention provides improved resistance to the harmful effects of vibration.

Abstract: An invention is disclosed in which a fluidic counter generates fluidic switching signals in response to a fluidic oscillator for sequentially activating a plurality of fluidically activated electrical switches for multiplexing a plurality of electrical conductors into a single conductor.