Abstract: Isogrid structure (20) forms case (14) surrounding the fan blades (12) of the turbofan. A ballistic fabric (22) surrounds the case. Containment zones (30, 32, 34) at the forward end have isogrid ribs (38) extending other than circumferentially. In the rear support zone ribs (76) extend circumferentially stiffening the case against collapse.

Abstract: A first metal sheet (34) has openings (46) in registration with depressions (40) in a second contacting metal sheet (36). Each depression has a downstream wall (42) at an angle of 24.degree. from the plane of the sheets. A metering hole (56) in the depression amidst cooling air in a direction to first impinge against an overlaying portion (48) of the first plate, before it diffuses along the downstream wall.

Abstract: A premix gas nozzle has longitudinal tangential entrance slots to a cylindrical chamber. There is an axially increasing flow area toward the chamber outlet, with pilot fuel centrally introduced near the outlet. A lean mix low NOx fuel nozzle is thereby stabilized.

Abstract: Wire is wound from spool 10 onto drum 15 where a multiple strand rope is formed and gripped at multiple locations. The gripped rope is cut into individual bundles, one end of each bundle being bonded to join the wires of the bundle together. The tufts may then be used to form a brush seal.

Abstract: The double derivative of the gas generator shaft (16) is sensed and compared to upper and lower limits to determine breaches of these limits within a first predetermined time, in which case a first potential surge condition is declared. The derivative of torque, or the double derivative of shaft speed, of the power shaft (22) is sensed and compared to upper and lower limits to determine breaches of these limits within a second predetermined time, in which case a second potential surge condition is declared. If both a first and second potential surge condition is declared within a third predetermined time, an actual surge condition is declared.

Abstract: The test cell has a pressure recovery pipe (26) receiving air from the tested engine (14). Excess air is inherently induced into the pipe. A source flow path for this excess air is provided from within the pipe (36) back to the entrance the pipe passing through a perforated bulkhead (30). High local velocities of the recirculating air, resulting variable static pressures on the engine and uncertainty in the thrust measurement are avoided.

Abstract: Compressor 14 of a gas turbine engine has a final centrifugal stage 18 discharging air into annulus 20. Diffuser 20 are straight and of frustoconical shape receiving air from the annulus. A side cut produces opening 38 in the side of each diffuser. Much of the flow exits through, and is directed by these openings.

Abstract: Stator vanes (22) are potted within pockets (38) in composite inner shroud sections (36). The pocket depth is only that required for bond strength and vane damping. Ribs (48) extend inwardly and are adhesively bonded to the seal support ring (32,34) which carries abradable seal surface.

Abstract: Turbine blade (10) has a plurality of trailing edge discharge openings (28) discharging cooling air. The blade trailing edge has an increasing thickness "E" toward the tip end (16). Discharge openings with the shortened pressure wall "L" have lesser distances "L" toward the tip end.

Abstract: The spherical portions of two gimbal (18) mounted convergent flaps (26,28) have hub structures (24) of concentric hubs (54,56). A piston (38) within each hub carries an annular seal (36) which is urged into sealing contact with the spherical static structure (10).The hub communicates air to a plenum between the convergent flaps to cool the convergent flaps.

Abstract: The gas turbine engine nozzle has fifteen divergent flaps (18) secured to fifteen convergent flaps (14). Five external flaps (30), are each of a "V" shape, and surround the divergent flaps. The position of all flaps is adjustable (22) for varying the nozzle configuration. Arms (46,48) of the external flaps overlap, being parallel at the maximum overlap. The external flaps are slidably secured to the divergent flaps and move therewith.

Abstract: Tube 16 within airfoil 10 carries cooling air. Flow openings 28 in the tubes direct cooling air 29 against the airfoil inner surface 14. Protrusions 30 form extended surface in the form of segmented trip strips are located with segmented trip strips are located with at least same in registration with openings 28. The chamber 18 between the tube 16 and surface 14 has an increasing flow area toward air exit 20.

Abstract: An inner cowl 30 is attached to outer cowling 26. When it is opened it rotates around hinge line extension 36. Latch band 38 has an arcuate upper link 44 secured to anchor 40. A lower link 50 circumferentially slides around the cowl on opening. The latch 52 which secures the lower link is located in a lower gradient where it is visible and accessible.

Abstract: Panels (10, 12, 16, 20) are joined on several hinge axes (14-22, 18-24), and may fold around either axis. A spherical ball (26) fits within a ball receiving socket (28) in the corner of each panel. Sealing against leakage, from one side of the panels to the other, is accomplished at this multiple axis point.

Abstract: An exhaust nozzle has variable convergent flaps, ejector flaps, and short divergent flaps spaced inwardly from the ejector flaps, cooling air is introduced through the opening between the divergent and ejector flaps. When the nozzle is vectored, the size of the opening is increased in the region of the nozzle experiencing higher static pressure.

Abstract: The external flaps (32), which contain the ram air, continue to form a conical structure during vectoring. External flaps (32) are hinged to the unison ring (30) with ejector flaps (34) hinged to the external flaps. A scissors linkage ( 48 ) joins each ejector flap (34) to the adjacent external flops. A spaced slider connection (58) guides, from the ejector flaps (34), the divergent flaps (26) which are joined to the convergent flaps (20) with a universal joint (28).

Abstract: An integrated damper and windage cover 52 has a windage cover portion 56 cantilevered at the upstream end, free of contact with the blade platform 24, 32. The contact portion 54 is rigid and bears against the underside of the blade platform 24, spanning blade platform clearance 50.

Abstract: Low angle air directing slots in the tip of an airfoil are produced by forming an elongated electrode by forming notches on opposite sides of the electrode and performing electric discharge machine with the electrode. During machining the electrode is oriented and fed at an acute angle with respect to the surface of the airfoil tip to form an opening, and then rotating the electrode to a position increasingly perpendicular to the surface of the airfoil tip.

Abstract: A premix gas nozzle has longitudinal tangential entrance slots to a cylindrical chamber. There is an axially increasing flow area toward the chamber outlet, with pilot fuel centrally introduced near the outlet. A lean mix low NOx fuel nozzle is thereby stabilized.

Abstract: A fuel injector 14 passes through wall 10 to inject fuel into a hot supersonic air flow 12. Wedge seals 26, 28 seal against leakage in cooperation with injection air flow 37, being compressed within seal carrier 16. Face seals 30, 32 are compressed by cover plate 34. Inboard seals 26, 44 are preferably more porous than the outboard seals so that there is a leakage of cooling air through crevice 44.