Abstract: A gas turbine engine according to an exemplary aspect of the present disclosure includes, among other things, a fan section including a fan with a plurality of fan blades rotatable about an axis. Each of the plurality of fan blades includes a mid-span shroud and a speed change device in communication with the fan.

Abstract: A fan blade has an airfoil main body extending between a leading edge and a trailing edge. The airfoil also has suction and pressure sides. A cavity is formed into said main body, and receives a filler material. A cover closes off the cavity, and is attached to the main body, with the cover having a thickness defined in a direction perpendicular to the suction side. The main body has a spar which extends along the cavity, with a thickness of the spar at a central location between ends of the cavity which has a second thickness. A ratio of the first thickness to the second thickness is between 0.5 and 2. A fan rotor and a gas turbine engine are also disclosed.

Abstract: An example airfoil for a gas turbine engine includes a body having a first surface extending from a first edge to a second edge and a cavity disposed in the body. A first cover is at least partially disposed within the cavity. The first cover includes a first portion cooperates with a corresponding second portion. A second cover covers the first cover and forms at least a portion of the first surface with the body. The first cover is disposed between the body and the second cover. The first cover and the second cover have a different coefficient of thermal expansion than the body.

Abstract: A rotary blade is provided that includes a root, an airfoil, and a tip insert. The airfoil is attached to the root, and has a suction side surface, a pressure side surface, a leading edge, a trailing edge, a tip, and a slot disposed within the tip. The slot extends in a chordwise direction between the leading edge and trailing edge. The tip insert has a base end and a rub end. The base end of the tip insert is disposed within the slot. The rub end of the tip insert extends radially outward from the airfoil tip.

Abstract: An airfoil includes, among other possible things, a main body extending between a leading edge and a trailing edge. Channels are formed into the main body, with a plurality of ribs extending intermediate the channels. A cover skin is attached to the main body. The cover skin is welded to the main body at outer edges. An adhesive is placed between inner surfaces of the cover skin and the main body. The adhesive is deposited inwardly of the outer edges of the cover skin.

Abstract: A turbine engine component has an airfoil portion with a tip portion and the tip portion has at least one chamfered edge on one side. If desired, the tip portion may have a first chamfered edge on a first side and a second chamfered edge on a second side opposed to the first side. A flattened tip portion may extend between the first and second chamfered edges. A tip treatment may be applied to the flattened tip portion.

Abstract: An airfoil comprises an airfoil body with an internal cavity and inner and outer covers. The airfoil body defines a first major surface of the airfoil, and a rib extends along the internal cavity. The inner cover is bonded to the airfoil body over the internal cavity, and includes a coupling element extending along the internal cavity in cooperative engagement with the rib. The outer cover is bonded to the airfoil body over the inner cover, and defines a second major surface of the airfoil.

Abstract: A fan blade has a main body extending between a leading edge and a trailing edge. Channels are formed into the main body from an open side extending toward an opposed closed side. A plurality of ribs extending across the main body intermediate the channels, the fan blade has a dovetail, and an airfoil extending radially outwardly from said dovetail. A bottom surface of the channels is defined at the closed side of the channels. Sides of the channel merge into sides of the ribs, with a compound fillet at the bottom surface. A first radius of curvature is used along the bottom, and merging into at least a second radius of curvature at the sides. The first radius of curvature is larger than the second radius of curvature.

Abstract: A fan blade includes an airfoil with a leading edge and a trailing edge in a chordwise direction, a root and a tip in a spanwise direction; and a sheath with a solid portion to cover the leading edge and first and second flanks extending in the chordwise direction to bond to the pressure and suction sides of the airfoil, respectively. The dimensions of the sheath are varied with respect to the spanwise direction of the blade.

Abstract: A fan blade comprises an airfoil portion and a sheath portion. The sheath portion has a sheath head section, a first sheath flank, and a second sheath flank, both flanks extending chordwise from the forward sheath section. The sheath portion is bonded to the airfoil portion such that the sheath head section covers the forward airfoil edge, defining a blade leading edge. The first sheath flank covers a portion of the first airfoil surface proximate the airfoil forward edge, jointly defining a blade suction surface. The second sheath flank covers a portion of the second airfoil surface proximate the airfoil forward edge, jointly defining a blade pressure surface. The first metallic material is an aluminum alloy containing between about 0.5 wt % and about 3.0 wt % of lithium.

Abstract: A two part airfoil has a suction side, a pressure side, a rib extending from one of the pressure side or the second side, the rib having a groove therein, and a riblet extending from an other of the pressure side or the suction side, the riblet fitting within the groove.

Abstract: A blade includes a hollow metal airfoil having an opening to an internal cavity in a first major surface. A metal cover is adhesively bonded to a socket formed around the opening. The cover encloses the cavity and provides a continuous first major surface.

Abstract: A hollow fan blade for a gas turbine engine provides improved resistance to buckling without adding wall thickness. The hollow fan blade includes a pressure side wall and a suction side wall separated and supported by ribs. In the present invention, each wall segment between each adjacent pair of ribs is straight, not curved. At least some of the adjacent walls segments extend at non-parallel angles relative to one another to form the airfoil shape to the hollow fan blade. The resulting fan blade side walls have faceted surfaces, rather than a continuous smooth, curved surface. The straight wall segments between adjacent ribs can withstand higher compressive forces without buckling. As a result, the wall thickness can be reduced.

Abstract: Hollow fan blades for turbo fan gas turbine engines are formed of two separate detail halves. Each detail half has a plurality of cavities machined out to reduce weight and form ribs. The ribs extend continuously and without intersecting one another in order to facilitate machining. The ribs extend in different directions in different regions of the detail half. In at least one region, the ribs extend in a serpentine pattern, such that concatenated rib segments are substantially perpendicular to one another, thereby providing stiffness in multiple directions.

Abstract: Hollow fan blades for turbo fan gas turbine engines are formed of two separate detail halves. Each detail half has a plurality of cavities and ribs machined out to reduce weight. The floor and opposite interior walls of each cavity are machined simultaneously. The configuration minimizes the number of cutter plunge cuts for the internal cavities, and maximizes cutter size, in order to minimize the time required to machine them. These detail halves are subsequently bonded and given an airfoil shape in the forming operation.

Abstract: A process for protecting an article using an anti-icing coating includes the steps of applying upon at least one surface of an article an anti-icing composition comprising at least one polysiloxane free of additives; and curing the anti-icing composition to form an anti-icing coating exhibiting an ice shear strength of about 19 kPA to about 50 kPa.

Abstract: A hollow fan blade for a gas turbine engine provides improved resistance to buckling without adding wall thickness. The hollow fan blade includes a pressure side wall and a suction side wall separated and supported by ribs. In the present invention, each wall segment between each adjacent pair of ribs is straight, not curved. At least some of the adjacent walls segments extend at non-parallel angles relative to one another to form the airfoil shape to the hollow fan blade. The resulting fan blade side walls have faceted surfaces, rather than a continuous smooth, curved surface. The straight wall segments between adjacent ribs can withstand higher compressive forces without buckling. As a result, the wall thickness can be reduced.

Abstract: Hollow fan blades for turbo fan gas turbine engines are formed of two separate detail halves. Each detail half has a plurality of cavities machined out to reduce weight and form ribs. The ribs extend continuously and without intersecting one another in order to facilitate machining. The ribs extend in different directions in different regions of the detail half. In at least one region, the ribs extend in a serpentine pattern, such that concatenated rib segments are substantially perpendicular to one another, thereby providing stiffness in multiple directions.

Abstract: Hollow fan blades for turbo fan gas turbine engines are formed of two separate detail halves. Each detail half has a plurality of cavities and ribs machined out to reduce weight. These detail halves are subsequently bonded and given an airfoil shape in the forming operation. In the present invention, the ribs are oriented biased to provide stiffness as needed in different sections of the fan blade with smooth transitions between regions. The ribs and cavities do not run solely radially or chordwise, but curve and change direction. The path of each cavity is curved sufficiently to eliminate any regions with long, straight cavities, which would have low inertia in cross sections through the cavity parallel to the rib. Preferably, cavities do not continue straight in any direction for lengths greater than half the blade chord (e.g. leading edge to trailing edge) before curvature causes the rib to intersect cross section.

Abstract: A hollow fan blade for turbo fan gas turbine engines is formed of two separate detail halves. Each detail half has a plurality of cavities and ribs machined out to reduce weight. These detail halves are subsequently bonded and given an airfoil shape in the forming operation. The present invention provides a hollow fan blade with internal cavity and rib geometry with improved durability that permits the bonding and forming to be performed without the need for gas pressurization. The ability to form the hollow fan blade of the present invention without gas pressurization is a result of the cavity and rib geometry and the orientation of the ribs. The ribs are tapered and transition into a compound radius of the floor that simulates the classical arch design element. The orientation of the ribs is generally in a parallel plane with the load vector that results from forming loads during the pre-form and final form operations.