Abstract: A vanity mirror assembly has a protective cover (7) which pivots with respect to a mirror frame (6) by virtue of a hinge arrangement consisting of a pivot arm (8), attached to the cover (7), snap-fitted to a pivot axle 14, attached to the frame (6). The cover (7) can be positioned and held in either a closed position, totally covering the mirror, or in one or more predetermined open positions. The cover is held in place by a band-type spring acting against a cam surface located on the pivot arm (8).

Abstract: Augmenting ribs (40) of zig-zag configuration are provided on a heat transfer surface (38) for increasing local heat transfer in a selected zone (68,70) of the surface (38).

Abstract: An atomizer having a central gas discharge conduit (112) and an annular, coaxial liquid conduit (120) includes a surrounding, annular liquid discharge opening (122) disposed immediately downstream of the gas discharge opening (116). A sized outlet orifice (131) is provided for discharging the comingled gas and liquid from the nozzle, with the orifice area (131) being sized no greater than the gas discharge opening (116).

Abstract: A method and system for controlling the position of a variable pitch vane stage (34) in a gas turbine engine (10) uses a feedback loop comparing the current compressor pressure ratio to a reference compressor pressure ratio. The reference pressure ratio is determined from a plurality of current engine operating parameters which identify a unique point on the compressor operating line.

Abstract: A rotor blade (1) is disclosed which recenters itself in relation to the rotatable hub in which it is installed. Imposition of an external force (A) upon the rotor blade (1) creates a moment (M) which acts about the rotor blade's root (2). Recentering is accomplished by centrifugal forces acting through an offset distance (C) resulting from rotation of the blade root (2) about a shaped retaining pin (6), achieving an enhanced opposing restorative moment (M') on the rotor blade (1). The rotor blade (1) contains an arcuate bearing suface (8) within a chordwisely disposed slot (7) in the rotor blade's root (2). This arcuate surface (8) bears against a mating arcuate surface (9) with a smaller radius of curvature lengthwise disposed on the shaped retaining pin (6).

Abstract: A method for scheduling the flow of cooling air to a gas turbine engine achieves a varying clearance between the turbine blade tips and surrounding annular shroud responsive to the current engine power level. Excess clearance is provided during operation at less than maximum normal engine power to accommodate the transient decrease in clearance following a step change in engine power level.

Abstract: A gas turbine engine (10) is provided with a bypass conduit (56) for venting air (52) leaking past a rotating compressor seal (46). The leakage air (58) is returned to the working fluid flow path (64) upstream of this first turbine stage (32).

Abstract: A combined fuel distribution and flameholding system (14) includes an improved spraybar (16) having a tapered portion (28) and a radially inwardly disposed tip portion (30). The tapered portion (28) is configured to provide a flow profile (26) diminishing with respect to inward radial displacement from the burner wall (32) for achieving a uniform blockage to free flow area ratio within the burner. The tip portion (30) creates a turbulent or pilot region (32) in the center of the burner, providing a local environment well suited for ignition and low load burner operation. The individual bars (16) are releasable (46) from the exterior of the burner for allowing longitudinal withdrawal of the entire spraybar (16) through a corresponding opening (48) in the burner wall (22).

Abstract: A method for controlling radial clearance in a gas turbine engine (10) uses a mathematical algorithm to synthesize the current clearance .delta., including the transient effects of prior engine operations. The synthesized clearance is compared (202) to a schedule of desired clearance (206) for closing .delta. a cooling air modulating valve (44) as required to avoid rubbing between the rotating blade tips and surrounding shroud.

Abstract: An optical positioning method and system (1) indicates achievement of a desired distance between a sprayhead (2) and a workpiece (4). The desired distance is indicated when a primary light pattern (16) converges with a secondary light pattern (20) directed from other than a coaxial orientation. A procedure for programming a workpiece's contours is described, which also allows for visual verification of the program.

Abstract: A radial flameholder (18) extends from the augmentor case (22) through an opening (30) in a coaxial liner (20) and into the hot exhaust gas stream (26). A portion of a cool, annular fan air stream (28) enters an upstream facing opening (34) and discharged radially inwardly adjacent the downstream edge (44) of the liner opening (30). The inner flow (42) of cool air protects the liner (20) downstream of the flameholder (18) by both cooling the liner (20) locally and by displacing the combustion reaction (32) attached to the flameholder (18).

Abstract: A method and fixture (10) for assembling compliant seals (30) includes an aligning member (12) having a grooved surface (14) for receiving a plurality of loose bristle elements (16). The bristle elements (16) are received within the grooves (26) and aligned thereby. First and second backing rings (20, 22) sandwich the aligned bristles (16) and are clamped by first and second clamping members (18, 24). The clamped rings (20, 22) and bristle elements (16) are then removed from the aligning member (12) and permanently secured together, forming the finished seal (30).

Abstract: A separating inlet duct (14) is provided with a reduced arm, bypass throat section (46) to restrict the bypass flow (18b) during periods of high speed aircraft flight. An ejector (34) ensures a minimum bypass flow (18b) during hover or low speed flight. An icing resistance baffle (40) having a rounded leading edge (42) defines the sized throat section (46).

Abstract: A fiber reinforced glass composite article is disclosed. The article comprises from about 20 volume percent to about 50 volume percent of a glass or glass ceramic matrix, from about 5 volume percent to about 50 volume percent monofilament fiber reinforcement and from about 15 volume percent to about 50 percent yarn fiber reinforcement. The monofilament fiber reinforcement and yarn fiber reinforcement are selectively distributed in the glass matrix to provide a fiber reinforced composite article which exhibits high tensile strength, high elastic modulus, high fracture toughness.

Abstract: A method and system (1) for adjusting the curvature of an electrical relay armature (4), and the energizing voltage level of the electrical relay (2) in which it is contained, is disclosed. The adjustment system (1) uses a rotatable carrier (16) from which an extendable cam (22) with a shaped bearing surface (23) directly communicates with, and provides necessary adjustment to, a curved armature section (8) of a misconfigured relay armature (4). The necessary adjustment is determined and controlled by a controller in combination with an energizing level determining device.

Abstract: A self-locking pitch change actuator is configured to fit within an annular hub (34). A ring gear (40) is driven circumferentially by a tangentially oriented ballscrew (42) and traveler (44). The ballscrew (42) is driven by a hydraulic motor (50) controlled responsive to an electric pitch change motor (74). A pitchlock (62) is positioned by the collective actions of the ballscrew (42) and pitch change motor (74), with any movement relative to a preselected null position driving the hydraulic motor beta control valve (60) into an operative position.

Abstract: A segmented heat shield (36) is provided for an annular combustor bulkhead (20). The shield segments (38) define a backside cooling volume (44) which receives a flow of cooling air (66) for protecting the shield segment (38) from the high temperature combustion reaction (34). A region of extended heat transfer surface (68) on the shield backside (42) increases heat transfer effectiveness, while backside raised ridges (60, 62, 64) direct the cooling air (66) for achieving a more even distribution before being exhausted (50) adjacent the combustor liners (12, 14).

Abstract: An adjustable spacer (20) is located in a unison ring (16) disposed about a gas turbine engine case (18). The spacer (20) includes a pad bolt (44) having a flattened surface (52) for contacting the case (18). The pad bolt (44) is adjusted radially by a threaded cylinder (28) and adjusting nut (36). The assembly is locked in place by a locknut (54) which includes a frangible link (72) for separating a headed portion (70) from a threaded portion (68).

Abstract: A ring gear (20) rotates circumferentially about a plain bearing (22) secured to the housing (10) of a centrifugal gas compressor. The ring gear (20) drives sector gears (18) for positioning variable guide vanes (14). A lever arm (32), actuator (36) and linkage (38, 40, 50) is provided for driving the ring gear (20).

Abstract: A family of airfoil cross sections, termed SC21xx, for use in a helicopter blade is disclosed. The airfoil (36) achieves maximum lift performance equivalent to prior art airfoil configurations without incurring increased aerodynamic drag at high velocities. The airfoil (36) was developed by thickening and drooping the leading edge region (38) of the prior art airfoil (30) improving lift in the leading edge region (38) and delaying the formation of sonic shock waves at high velocities.