Abstract: A gas turbine engine according to an exemplary aspect of the present disclosure includes, among other things, a passageway configured to permit fluid to drain back into a bearing compartment. The passageway has an inlet outside the bearing compartment and an outlet inside the bearing compartment. The outlet is spaced-apart from a central rotational axis of a towershaft gear.

Abstract: An airfoil bonding system may comprise a mold tool configured to support an airfoil assembly during a bonding process. The bonding process may include applying heat and pressure to the airfoil assembly. A surface of the mold tool may complement a preselected airfoil parameter. The mold tool may maintain the airfoil assembly in the preselected airfoil parameter during the application of heat and pressure to the airfoil assembly.

Abstract: A gas turbine engine according to an exemplary aspect of the present disclosure includes, among other things, a passageway configured to permit fluid to drain back into a bearing compartment. The passageway has an inlet outside the bearing compartment and an outlet inside the bearing compartment. The outlet is spaced-apart from a central rotational axis of a towershaft gear.

Abstract: A cantilevered airfoil includes, among other things, an airfoil having a body section and a tip, the body section extending in a first direction that is angled relative to a radial direction, the tip of the airfoil angled radially in a second direction relative to the body section.

Abstract: An airfoil bonding system may comprise a mold tool configured to support an airfoil assembly during a bonding process. The bonding process may include applying heat and pressure to the airfoil assembly. A surface of the mold tool may complement a preselected airfoil parameter. The mold tool may maintain the airfoil assembly in the preselected airfoil parameter during the application of heat and pressure to the airfoil assembly.

Abstract: A cantilevered airfoil includes, among other things, an airfoil having a body section and a tip, the body section extending in a first direction that is angled relative to a radial direction, the tip of the airfoil angled radially in a second direction relative to the body section.

Abstract: A gas turbine engine rotor drum includes spaced apart discs providing a cavity between the discs. The discs are configured to rotate in a rotational direction about an axis. An annular support is mounted on at least one of the discs and within the cavity. A cascade of relatively short anti-vortex members is mounted circumferentially on the annular support. The anti-vortex members include an outer end having a concave surface extending within the cavity radially outward from the annular support. The concave surface faces the rotational direction and promotes swirl as the rotor drum rotates.

Abstract: A gas turbine engine rotor drum includes spaced apart discs providing a cavity between the discs. The discs are configured to rotate in a rotational direction about an axis. An annular support is mounted on at least one of the discs and within the cavity. A cascade of relatively short anti-vortex members is mounted circumferentially on the annular support. The anti-vortex members include an outer end having a concave surface extending within the cavity radially outward from the annular support. The concave surface faces the rotational direction and promotes swirl as the rotor drum rotates.

Abstract: A gas turbine engine rotor drum includes spaced apart discs providing a cavity between the discs. The discs are configured to rotate in a rotational direction about an axis. An annular support is mounted on at least one of the discs and within the cavity. A cascade of relatively short anti-vortex members is mounted circumferentially on the annular support. The anti-vortex members include an outer end having a concave surface extending within the cavity radially outward from the annular support. The concave surface faces the rotational direction and promotes swirl as the rotor drum rotates.

Abstract: A gas turbine engine rotor drum includes spaced apart discs providing a cavity between the discs. The discs are configured to rotate in a rotational direction about an axis. An annular support is mounted on at least one of the discs and within the cavity. A cascade of relatively short anti-vortex members is mounted circumferentially on the annular support. The anti-vortex members include an outer end having a concave surface extending within the cavity radially outward from the annular support. The concave surface faces the rotational direction and promotes swirl as the rotor drum rotates.

Abstract: Rolling element bearings capable of both axial and radial restraint are readily removably mounted on the shaft of each screw rotor so as to allow a clearance type radial fit between the bearing and shaft. A washer engages the inner race of the bearing which also engages a shim. A bolt squeezes the inner race between the washer and shim to secure the bearing in place while the shim thickness/height determines the position of the rotor within the casing.

Abstract: Normally closed valve structure is located in a fluid path between the suction and discharge sides of a compressor. The valve structure opens upon a small pressure differential when the higher pressure is in the normal suction side which is indicative of reverse operation. Additionally, relief valve structure opens when the discharge pressure becomes excessive.

Abstract: Rolling element bearings capable of both axial and radial restraint are readily removably mounted on the shaft of each screw rotor so as to allow a clearance type radial fit between the bearing and shaft. A washer engages the inner race of the bearing which also engages a shim. A bolt squeezes the inner race between the washer and shim to secure the bearing in place while the shim thickness/height determines the position of the rotor within the casing.

Abstract: An unbiased valve is located within a muffler. The valve is positioned by the pressure differential across the valve and is either in the full open or full closed position. A pressure equalization tube is provided between the downstream cavity of the muffler and the back of the valve such that flow pattern produced low pressure areas are avoided and the valve can react to actual pressure differentials in the flow.