A passive elastic teeter bearing (3c) for an aircraft rotor (3b), including, rotatably arranged on an rotational axis (RA) of said rotor (3b), a teeter beam (3d), configured for attaching the rotor which has rotor blades, with the teeter beam being configured for performing a teetering motion, and having two pairs of first lugs (3j1, 3j2) arranged at opposite ends thereof at a distance with respect to the rotational axis; and a hub piece (3f) located below the teeter beam, the hub piece having two arms (3g1, 3g2) that extend outwardly in a radial direction, each having a second lug (3k) arranged at a distance with respect to said rotational axis. Each second lug is located between the two lugs of a respective pair of first lugs, and respective connecting pins (3n) pass through the first and second lugs on either side of the rotational axis. A pair of elastic bushings (3l1, 3l2) are arranged on each connecting pin between a first one of the first lugs and the second lug and between a second one of said first lugs and the second lug, respectively.

A rotor assembly comprises a rotor hub and rotor-blade assemblies. The rotor hub comprises rotor-blade supports. Each rotor-blade assembly is coupled to a respective one of the rotor-blade supports and comprises a flap axle, a hub connector, a rotor blade, and a torsion strap. The flap axle extends through a respective one of the rotor-blade supports and has a central flap-axle axis. The hub connector is pivotable relative to a rotor-blade support about the central flap-axle axis and defines a central hub-connector axis. The rotor blade is coupled to and is pivotable relative to the hub connector, and, together with the hub connector, is pivotable relative to a respective one of the rotor-blade supports about the central flap-axle axis. The torsion strap has a first end, coupled to the rotor blade, and a second end, through which the flap axle passes.

A rotor assembly comprises a rotor hub and rotor-blade assemblies. The rotor hub comprises rotor-blade supports. Each rotor-blade assembly is coupled to a respective one of the rotor-blade supports and comprises a flap axle, a hub connector, a rotor blade, and a torsion strap. The flap axle extends through a respective one of the rotor-blade supports and has a central flap-axle axis. The hub connector is pivotable relative to a rotor-blade support about the central flap-axle axis and defines a central hub-connector axis. The rotor blade is coupled to and is pivotable relative to the hub connector, and, together with the hub connector, is pivotable relative to a respective one of the rotor-blade supports about the central flap-axle axis. The torsion strap has a first end, coupled to the rotor blade, and a second end, through which the flap axle passes.

A laminated elastomeric journal bearing has an outer sleeve having an inner surface, at least a portion of each end of the inner surface being a concave surface of revolution, and an inner sleeve having an outer surface, at least a portion of each end of the outer surface being a convex surface of revolution. Alternating layers of elastomer and metal are located between the sleeves, with adjacent surfaces of the layers and the sleeves being adhered to each other.

A rotor blade retention assembly is configured to connect a rotor blade to a central hub comprising a hub arm coupled to and extending radially outward from a hub bowl. The hub arm includes a hub arm lug. The rotor blade retention assembly includes a tension-torsion strap with an inboard end and an outboard end, the inboard end including an inboard pin hole and the outboard end including an outboard pin hole. The rotor blade retention assembly further includes an inboard blade pin and an outboard blade pin. The inboard blade pin is configured to extend through the hub arm lug and the inboard pin hole and to couple the inboard end of the tension-torsion strap to the hub arm. The outboard blade pin is configured to extend through a blade lug of a rotor blade and the outboard pin hole and to couple the outboard end of the tension-torsion strap to the rotor blade.

A rotor blade retention assembly is configured to connect a rotor blade to a central hub comprising a hub arm coupled to and extending radially outward from a hub bowl. The hub arm includes a hub arm lug. The rotor blade retention assembly includes a tension-torsion strap with an inboard end and an outboard end, the inboard end including an inboard pin hole and the outboard end including an outboard pin hole. The rotor blade retention assembly further includes an inboard blade pin and an outboard blade pin. The inboard blade pin is configured to extend through the hub arm lug and the inboard pin hole and to couple the inboard end of the tension-torsion strap to the hub arm. The outboard blade pin is configured to extend through a blade lug of a rotor blade and the outboard pin hole and to couple the outboard end of the tension-torsion strap to the rotor blade.

A rotor system includes a drive hub, a set of rotor blades extending radially from the drive hub, and a set of tension-torsion straps connecting the rotor blades to the drive hub. The drive hub has a rotor mast opening extending along a mast axis. The rotor system is configured to rotate about the mast axis. The drive hub further has a set of mounting slots for mounting the tension-torsion straps. The mounting slots are arranged along a circle around the drive hub, each mounting slot extending through the drive hub along a respective mounting axis. The mounting axis of each of the mounting slots is biased relative to the mast axis. The tension-torsion straps are mounted to the drive hub at their corresponding mounting slots.

A rotor system includes a drive hub, a set of rotor blades extending radially from the drive hub, and a set of tension-torsion straps connecting the rotor blades to the drive hub. The drive hub has a rotor mast opening extending along a mast axis. The rotor system is configured to rotate about the mast axis. The drive hub further has a set of mounting slots for mounting the tension-torsion straps. The mounting slots are arranged along a circle around the drive hub, each mounting slot extending through the drive hub along a respective mounting axis. The mounting axis of each of the mounting slots is biased relative to the mast axis. The tension-torsion straps are mounted to the drive hub at their corresponding mounting slots.

An exemplary rotorcraft lockout system includes a main rotor lockout comprising a base operable to be attached to a bottom surface of a fuselage and a first and a second tension arm operable to be connected to the base and a main rotor hub, and a tail rotor lockout including a clamp operable to connect to a horizontal stabilizer, a rotor arm connector operable to connect to a tail rotor hub, and a tail rotor tension arm operable to interconnect the clamp and the rotor arm connector in tension.

An exemplary rotorcraft lockout system includes a main rotor lockout comprising a base operable to be attached to a bottom surface of a fuselage and a first and a second tension arm operable to be connected to the base and a main rotor hub, and a tail rotor lockout including a clamp operable to connect to a horizontal stabilizer, a rotor arm connector operable to connect to a tail rotor hub, and a tail rotor tension arm operable to interconnect the clamp and the rotor arm connector in tension.