Abstract: A method for assembling a gas turbine engine includes providing a first fan assembly configured to rotate in a first rotational direction, rotatably coupling a second fan assembly to the first fan assembly, wherein the second fan assembly is configured to rotate in a second rotational direction that is opposite the first rotational direction, and coupling a lubrication system to the gas turbine engine such that a lubrication fluid is channeled through at least a portion of the second fan assembly.

Abstract: An aircraft engine turbine frame includes a first structural ring, a second structural ring disposed co-axially with and radially spaced inwardly of the first structural ring about a centerline axis. A plurality of circumferentially spaced apart struts extend between the first and second structural rings. Forward and aft sump members having forward and aft central bores are fixedly joined to forward and aft portions of the turbine frame respectively. A frame connecting means for connecting the engine to an aircraft is disposed on the first structural ring. The frame connecting means may include a U-shaped clevis. The frame may be an inter-turbine frame axially located between first and second turbines of first and second rotors of a gas turbine engine assembly. An axial center of gravity of the second turbine passes though or very near a second turbine frame bearing supported by the aft sump member.

Abstract: An aircraft gas turbine engine includes high and low pressure turbines having respective counter rotatable low pressure inner and outer rotors with low pressure inner and outer shafts in part rotatably disposed co-axially within a high pressure rotor and drivingly connected to first and second fan blade rows and first and second boosters respectively. A bypass duct radially bounded by a fan casing and an annular radially inner bypass duct wall surrounds the boosters axially located between the first and second fan blade rows. The engine has a high pressure compressor operable to produce an overall pressure ratio in a range of about 40-65 and a fan inlet hub to tip radius ratio in a range between 0.20 and 0.35, a bypass ratio in a range of 5-15, an operational fan pressure ratio in a range of 1.4-2.5, and a sum of operational fan tip speeds in a range of 1000 to 2500 feet per second.

Abstract: An aircraft engine turbine frame includes a first structural ring, a second structural ring disposed co-axially with and radially spaced inwardly of the first structural ring about a centerline axis. A plurality of circumferentially spaced apart struts extend between the first and second structural rings. Forward and aft sump members having forward and aft central bores are fixedly joined to forward and aft portions of the turbine frame respectively. A frame connecting means for connecting the engine to an aircraft is disposed on the first structural ring. The frame connecting means may include a U-shaped clevis. The frame may be an inter-turbine frame axially located between first and second turbines of first and second rotors of a gas turbine engine assembly. An axial center of gravity of the second turbine passes though or very near a second turbine frame bearing supported by the aft sump member.

Abstract: An aircraft gas turbine engine assembly includes an inter-turbine frame axially located between high and low pressure turbines. Low pressure turbine has counter rotating low pressure inner and outer rotors with low pressure inner and outer shafts which are at least in part rotatably disposed co-axially within a high pressure rotor. Inter-turbine frame includes radially spaced apart radially outer first and inner second structural rings disposed co-axially about a centerline and connected by a plurality of circumferentially spaced apart struts. Forward and aft sump members having forward and aft central bores are fixedly joined to axially spaced apart forward and aft portions of the inter-turbine frame. Low pressure inner and outer rotors are rotatably supported by a second turbine frame bearing mounted in aft central bore of aft sump member. A mount for connecting the engine to an aircraft is located on first structural ring.

Abstract: An aircraft gas turbine engine assembly includes an inter-turbine frame axially located between high and low pressure turbines. Low pressure turbine has counter rotating low pressure inner and outer rotors with low pressure inner and outer shafts which are at least in part rotatably disposed co-axially within a high pressure rotor. Inter-turbine frame includes radially spaced apart radially outer first and inner second structural rings disposed co-axially about a centerline and connected by a plurality of circumferentially spaced apart struts. Forward and aft sump members having forward and aft central bores are fixedly joined to axially spaced apart forward and aft portions of the inter-turbine frame. Low pressure inner and outer rotors are rotatably supported by a second turbine frame bearing mounted in aft central bore of aft sump member. A mount for connecting the engine to an aircraft is located on first structural ring.

Abstract: An aircraft gas turbine engine includes high and low pressure turbines having respective counter rotatable low pressure inner and outer rotors with low pressure inner and outer shafts in part rotatably disposed co-axially within a high pressure rotor and drivingly connected to first and second fan blade rows and first and second boosters respectively. A bypass duct radially bounded by a fan casing and an annular radially inner bypass duct wall surrounds the boosters axially located between the first and second fan blade rows. The engine has a high pressure compressor operable to produce an overall pressure ratio in a range of about 40-65 and a fan inlet hub to tip radius ratio in a range between 0.20 and 0.35, a bypass ratio in a range of 5-15, an operational fan pressure ratio in a range of 1.4-2.5, and a sum of operational fan tip speeds in a range of 1000 to 2500 feet per second.

Abstract: An aircraft engine turbine frame includes a first structural ring, a second structural ring disposed co-axially with and radially spaced inwardly of the first structural ring about a centerline axis. A plurality of circumferentially spaced apart struts extend between the first and second structural rings. Forward and aft sump members having forward and aft central bores are fixedly joined to forward and aft portions of the turbine frame respectively. A frame connecting means for connecting the engine to an aircraft is disposed on the first structural ring. The frame connecting means may include a U-shaped clevis. The frame may be an inter-turbine frame axially located between first and second turbines of first and second rotors of a gas turbine engine assembly. An axial center of gravity of the second turbine passes though or very near a second turbine frame bearing supported by the aft sump member.

Abstract: A recirculation passageway for a turbine engine provides stall protection in a booster by directing high pressure airflow from a flow path of the booster to the passageway. The high pressure airflow loses energy and decreases in pressure while traveling through the passageway until re-entry into the booster flow path. The airflow recirculates in the passageway until the airflow is discharged through a high pressure compressor.

Abstract: A turbine engine including an oil flow path through the low pressure system shaft which, as compared to at least one known oil flow path, facilitates increasing the rated torque and life of the low pressure system shaft is described. In one embodiment, the lubrication opening in the low pressure shaft is oriented so that with respect to a plane along which an outer surface of the low pressure shaft substantially extends, the center axis of the lubrication opening is substantially normal to the plane. As a result of this configuration, the stress concentration in the low pressure shaft at the location of the lubrication opening is substantially reduced. In addition, such a lubrication opening is relatively easy to form as compared to the known, angularly oriented lubrication shaft.