A gas turbine engine includes a core turbine engine and a fan mechanically coupled to the core turbine engine. The fan includes a plurality of fan blades, each fan blade defining a base and an inner end along a radial direction of the gas turbine engine. The fan also includes a hub covering the base of each of the plurality of fan blades. Further, the fan includes one or more bearings for supporting rotation of the plurality of fan blades. The one or more bearings define a fan bearing radius along a radial direction of the gas turbine engine. Similarly, the hub defines a hub radius along the radial direction of the gas turbine engine. The ratio of the hub radius to the fan bearing radius is less than about three, providing for desired packaging of the various components within the fan of the gas turbine engine.

A variable pitch fan for a propulsion device is provided. The variable pitch fan includes a plurality of fan blades coupled to a disk and a rotatable front hub covering the disk. Each fan blade is rotatable about a pitch axis to vary a pitch of the fan blade. The pitch is variable within a pitch range that is at least about 80 to about 130. Each fan blade extends radially outward from the disk along a span from a root to a tip. A portion of the span adjacent the root defines a root span region, a portion of the span adjacent the tip defines a tip span region. A solidity of the variable pitch fan is at least 1.0 in the root span region.

A variable pitch fan for a gas turbine engine includes a fan blade defining a pitch axis and attached at a radially inner end to a trunnion mechanism. The variable pitch fan also includes a disk having a disk segment with the trunnion mechanism extending at least partially through the disk segment. A key is positioned at least partially in a key slot defined in a base of the trunnion mechanism, and further positioned adjacent to a support member of the disk segment. The key defines a first contact line between the key and the key slot and a second contact line between the key and the support member. The first and second contact lines respectively define a first contact reference line in a second contact reference line. The first and second contact reference lines define an angle with the pitch axis of the fan blade greater than zero degrees and less than ninety degrees.

The invention concerns a device (1) for controlling the pitch of the blades of a fan (4) rotor (3), comprising a radial shaft (6) linked to the blade, a connection rod (8) of which the axial movement controls the rotation of the radial shaft (6), characterized in that it comprises:a first part (10) that is mobile in rotation with the rotor (3) about the axis (11) of the fan (4), and on which one end of each connection rod (8) is secured,a second part (12) linked to the first part (10), andat least three cylinders (14) capable of moving said second part (12) in axial translation, and of varying the tilt of said second part, the translation and tilt of the second part (12) driving a corresponding translation and tilt of the first part (10), such that, when the first part (10) rotates, each connection rod (8) is subject to axial displacement of which the amplitude is variable and is a function of the tilt of the first part (10), making it possible to vary the pitch of the blade during the rotation of same. The invention also concerns a fan, and a method for controlling the pitch of blades.

A variable pitch fan for gas turbine engine is provided. The variable pitch fan includes a plurality of fan blades rotatably coupled to a disk and an actuation assembly for changing a pitch of each of the plurality of fan blades. The actuation assembly generally includes an actuation member operably connected to at least one of the plurality of fan blades and a pin. The pin is movable between a first position in which the pin is positioned at least partially in a channel defined in the actuation member, and a second position. The pin blocks movement of the actuation member relative to the pin past a range defined by the channel when in the first position. The actuation assembly further includes a retraction system for selectively engaging the pin in moving the pin from the first position to the second position.

A fan assembly for an engine has a fan blade, a disk having a disk segment, a trunnion mechanism having a trunnion extending at least partially through the disk segment, and first and second attachment systems. The trunnion has a platform and a shaft. The fan blade is adjacent to the platform of the trunnion. The trunnion is attached to the disk segment using the first attachment system along a preload path. The first and second attachment systems further include first and second retention features, respectively, separate from the preload path. During normal operation of the fan assembly, the first attachment system retains the trunnion within the disk along a first load path. Upon a failure in the trunnion, the first and second retention features together retain the trunnion within the disk segment along a second load path, the first load path being different than the second load path.

A trunnion-to-disk connection for use on an open fan configuration of a gas turbine engine may include an integral trunnion and blade spar inserted through a trunnion aperture of a fan disk and supported by top bearing and a bottom bearing. A cavity can be provided between a trunnion of the integral trunnion and blade spar and the fan disk, as well as between the top bearing and bottom bearing. Pressurized hydraulic fluid can be supplied to the cavity to urge the integral trunnion and blade spar in a direction to preload the bearings. Prior to pressurization, and prior to installation of the bottom bearing, the trunnion can be inserted into a trunnion aperture of the fan disk such that an end of the trunnion extends past the fan disk to provide sufficient space to insert the bottom bearing from within the open interior of the fan disk.

An axial air movement fan having a plurality of variable pitch fan blades (2), extending radially from a hub (4) rotatable about a main axis (3), each blade (2) further being pivotable about its radial axis to vary the blade pitch. The blades (2) each are mounted on an associated bearing (5) mounted on said hub, the bearing comprising a ball bearing having a first radially inner race (25) fast the blade (2) and a second radially outer race (26) rotationally fast to the hub (4). The balls (14) in the bearing are separated by separators (15), each separator being generally cylindrical and having its cylindrical axis coaxial with the orbital axis (22) of the orbit of the balls (14) and being adapted to rotate about the said orbital axis (22), the side faces of the separator each having a part spherical recess (16) adapted to receive a ball (14). Rotation of the separator (15) about the orbital axis (22) is such as to entrain lubricant in the bearing and to bias the lubricant from adjacent the outer race (26) over the balls (14) towards the inner race (25).

A propulsion system is provided, the propulsion system including a rotor assembly configured to rotate relative to the engine centerline axis, and wherein one or more blades of the rotor assembly are configured to rotate along a blade pitch angle axis. A vane assembly is positioned in aerodynamic relationship with the rotor assembly. The vane assembly includes one or more vanes, wherein each vane includes a vane pitch angle. A controller is configured to execute operations, the operations including moving each blade to a reverse thrust position about its respective blade pitch axis, and adjusting each vane about its respective vane pitch axis when the plurality of blades is in the reverse thrust position to modify an amount of reverse thrust generated by the propulsion system.

A fan has a rotating bulge defining a radially outermost point of the rotating cone relative to a rotational axis. The rotating bulge is defined by a radially outwardly extending forward portion leading to the radially outermost point on the bulge and then a radially inwardly extending portion aft of the radially outermost point of the bulge leading into the core engine path within the splitter housing. The core splitter housing has a leading edge, and the bulge radially outermost point being upstream of the leading edge of the splitter housing. The bulge radially outermost point is a first radial distance from a rotational axis, and the leading edge of the splitter housing being at a second radial distance of the rotational axis, and a ratio of the first radial distance to the second radial distance being at least 0.95.