A hinge assembly such as a lead-lag hinge can include a hinge pin assembly. The hinge pin assembly can include an outer cylinder, a shear pin that extends through the outer cylinder and having a first threaded end and a second threaded end, a first nut threaded on the first threaded end and a second nut threaded on the second end. An opposing force between the first nut and the second nut applies a compressive stress to the outer cylinder that may increase a resistance of the hinge pin assembly to wear and damage. In the case of complete failure of the outer cylinder, the shear pin can maintain structural integrity of the hinge pin assembly and of the hinge assembly.

A rotorcraft main rotor system, including a yoke, a rotor blade, and a grip assembly attaching the rotor blade to the yoke. The grip assembly includes a grip body formed from a contiguous laminated composite and has a substantially constant thickness, where the grip body has an upper extension, a lower extension and a connecting portion connected between an inboard end of the upper extension and an inboard end of the lower extension. An inside surface of the upper extension faces, and is substantially parallel to, an inside surface of the lower extension, and the upper extension has first features and the lower extension has second features that are aligned with the first features, where the first features and second features each include at least one of an edge contour, attachment holes, or first protective elements.

A rotorcraft main rotor system, including a yoke, a rotor blade, and a grip assembly attaching the rotor blade to the yoke. The grip assembly includes a grip body formed from a contiguous laminated composite and has a substantially constant thickness, where the grip body has an upper extension, a lower extension and a connecting portion connected between an inboard end of the upper extension and an inboard end of the lower extension. An inside surface of the upper extension faces, and is substantially parallel to, an inside surface of the lower extension, and the upper extension has first features and the lower extension has second features that are aligned with the first features, where the first features and second features each include at least one of an edge contour, attachment holes, or first protective elements.

A pitch horn assembly for an aircraft comprises a pitch horn rotatably coupled to a connector pin along a first axis using a first set of spherical bearings. The connector pin is rotatably coupled to a housing along a second axis using a second set of spherical bearings. A crank is fixedly coupled to the connector pin, wherein the pitch horn and the crank are configured to commonly rotate relative to the housing.

A bearing system includes an inboard bearing assembly and an outboard bearing assembly. The inboard bearing assembly includes an inboard fitting and an inboard race. The inboard fitting includes a plate with a convex mating surface and a first aperture formed through the plate for receiving a blade root of a rotor blade. The inboard race comprising a concave mating surface configured to receive the convex mating surface a second aperture formed the inboard race. The outboard bearing assembly includes an outboard bearing assembly comprising an outboard fitting having an aperture formed therethrough for receiving the blade root of the rotor blade.

A rotor assembly for a rotorcraft, comprising a rotor shaft, a torque transmission unit that is non-rotatably mounted to the rotor shaft, a rotor hub that is rotatably mounted to the rotor shaft via an associated angular displacement enabling component, and at least two rotor blades that are connected to the rotor hub, wherein the torque transmission unit is coupled to the at least two rotor blades on a rotor assembly outflow side via a pitch control unit, wherein the pitch control unit transmits to the at least two rotor blades torque that is applied from the rotor shaft to the torque transmission unit, and wherein the pitch control unit increases a respective pitch angle of the at least two rotor blades if the torque is increased.

A rotor assembly for a rotorcraft, comprising a rotor shaft, a torque transmission unit that is non-rotatably mounted to the rotor shaft, a rotor hub that is rotatably mounted to the rotor shaft via an associated angular displacement enabling component, and at least two rotor blades that are connected to the rotor hub, wherein the torque transmission unit is coupled to the at least two rotor blades on a rotor assembly outflow side via a pitch control unit, wherein the pitch control unit transmits to the at least two rotor blades torque that is applied from the rotor shaft to the torque transmission unit, and wherein the pitch control unit increases a respective pitch angle of the at least two rotor blades if the torque is increased.

A sleeve connecting a blade to the hub of a rotor of a rotary wing aircraft. The sleeve has a leading edge and a trailing edge, together with a protuberance arranged on the trailing edge. The dimensions of the protuberance are linked to the dimensions of the sleeve. The presence of the protuberance serves to improve the aerodynamic behavior of the sleeve and of the rotor during rotation of the rotor while the aircraft is moving forwards, both when the sleeve is advancing and when it is retreating. The presence of the protuberance also serves to reduce the vibration generated by a wake of the rotor on a tail boom or on a horizontal and/or vertical stabilizer of the aircraft.

A sleeve connecting a blade to the hub of a rotor of a rotary wing aircraft. The sleeve has a leading edge and a trailing edge, together with a protuberance arranged on the trailing edge. The dimensions of the protuberance are linked to the dimensions of the sleeve. The presence of the protuberance serves to improve the aerodynamic behavior of the sleeve and of the rotor during rotation of the rotor while the aircraft is moving forwards, both when the sleeve is advancing and when it is retreating. The presence of the protuberance also serves to reduce the vibration generated by a wake of the rotor on a tail boom or on a horizontal and/or vertical stabilizer of the aircraft.

The present invention relates to Tetracyclic Heterocycle Compounds of Formula ##STR00001##
and pharmaceutically acceptable salts or prodrug thereof, wherein A, X, R.sup.1, R.sup.2, R.sup.3 and Ware as defined herein. The present invention also relates to compositions comprising at least one Tetracyclic Heterocycle Compound, and methods of using the Tetracyclic Heterocycle Compounds for treating or preventing HIV infection in a subject.