Abstract: An elastic torsion element for connecting a rotor blade to a rotor hub of a rotor, the elastic torsion element comprising at least two elastically deformable plates, wherein each one of the at least two elastically deformable plates comprises fiber reinforced polymers, wherein respective fibers of the fiber reinforced polymers of each one of the at least two elastically deformable plates are at least arranged along one of a first and a second dominant fiber directions, wherein the first dominant fiber direction crosses the second dominant fiber direction in a predetermined fiber direction crossing region, and wherein the elastic torsion element comprises an integrated elastic lead-lag hinge that is formed at the predetermined fiber direction crossing region.

Abstract: A multirotor aircraft with an airframe and at least one wing that is mounted to the airframe, the at least one wing being provided with at least four thrust producing units that are arranged in spanwise direction of the at least one wing, wherein each one of the at least four thrust producing units comprises at least one rotor assembly that is accommodated in an associated shrouding, the associated shrouding being integrated into the at least one wing, wherein the associated shrouding defines an air duct that is axially delimited by an air inlet region and an air outlet region, wherein the air inlet region exhibits in circumferential direction of the air duct at least two different aerodynamic profiles.

Abstract: An elastic flapping hinge for connecting a rotor blade to a rotor hub of a rotary wing aircraft, comprising an elastic flapping hinge member arrangement that includes a hub attachment area for attachment to the rotor hub, a connection area for attachment to the rotor blade, and an elastic flapping hinge area that is arranged between the hub attachment area and the connection area and adapted to allow flapping movements, the elastic flapping hinge member arrangement comprising at least two elastic flapping hinge members having a first bending stiffness for flapping movements and a second bending stiffness for lead-lag movements, the first bending stiffness being smaller than the second bending stiffness, wherein the at least two elastic flapping hinge members diverge from each other in the elastic flapping hinge area by a predetermined divergence angle.

Abstract: A flexbeam unit comprising a plurality of flexbeam elements, each defining a load passing member that is attachable to a rotor hub associated with a rotor shaft of the multi-blade rotor, the plurality of flexbeam elements defining a predetermined number of torsion elements that are connectable with associated rotor blades of the multi-blade rotor, wherein at least one of the predetermined number of torsion elements comprises at least one first flexbeam element defining a first longitudinal direction and at least one second flexbeam element defining a second longitudinal direction, wherein the at least one first and second flexbeam elements are interconnected by a beam connector in a direction transverse to the first and/or second longitudinal directions.

Abstract: A thrust producing unit for producing thrust in a predetermined direction, comprising at least two rotor assemblies and a shrouding that accommodates at most one of the at least two rotor assemblies, wherein the shrouding defines a cylindrical air duct that is axially delimited by an air inlet region and an air outlet region, and wherein the air inlet region exhibits in circumferential direction of the cylindrical air duct an undulated geometry.

Abstract: In a rotary wing aircraft a bar (1) of composite matrix material has a longitudinal axis (8) perpendicular to a cross section with upper and lower surfaces (2, 3). At least one torsion box (17) comprises an upper and a lower layers (10, 21, 11, 22) respectively offset of a longitudinal axis (8) and of the upper and the lower surfaces (2, 3), said upper and lower layers (10, 21, 11, 22) being laterally joint, while cross sections are filled with the first group of fibers extending essentially parallel to the longitudinal axis (8).

Abstract: A flexbeam unit for a multi-blade rotor of a rotary wing aircraft, said flexbeam unit defining a predetermined number of torsion elements that are connectable with associated rotor blades, at least one torsion element comprising a flexbeam element having an associated longitudinal direction and comprising inner layers of a first fiber reinforced material that are embedded between outer layers of a second fiber reinforced material, said outer layers being composed of main plies comprising unidirectional fibers and said inner layers defining a cross section profile center in said associated longitudinal direction, said cross section profile center being composed of interconnected bias plies comprising fibers that are oriented transversely relative to said unidirectional fibers.

Abstract: A multi-blade rotor for a rotary wing aircraft, comprising a plurality of rotor that is connected to an associated rotor head via a plurality of flexbeam elements, wherein at least one flexbeam element of the plurality of flexbeam elements comprises an asymmetrical flexbeam root that is mounted to the associated rotor head.

Abstract: A flexbeam unit for a multi-blade rotor of a rotary wing aircraft, the flexbeam unit comprising a plurality of flexbeam elements that define a predetermined number of torsion elements and a ring-shaped connection zone for attachment to a rotor hub associated with a rotor shaft of the multi-blade rotor, each flexbeam element passing the ring-shaped connection zone in a tangential manner and uninterruptedly connecting a first torsion element to a second torsion element of the predetermined number of torsion elements, wherein each flexbeam element overlaps at least one in the circumferential direction of the ring-shaped connection zone immediately following flexbeam element and is overlapped by at least one in the circumferential direction of the ring-shaped connection zone immediately preceding flexbeam element.

Abstract: A rotor blade (1) with an exterior shell (20) extending in a span and chord wise direction and at least one control flap (4) extending in essentially span wise direction to said exterior shell (20). Load transmission means inside said blade chamber (7) comprise piling type housings (13) respectively with one actuator (8, 9), one flap drive (10, 11) and a longitudinal girder (15). Said at least one piling type housing (13) comprises at least one upper strap (14) and at least one lower strap (14) oriented essentially in said chord direction in between said longitudinal girder (15) on the one side and the support for said at least one actuator (8, 9) on the other side, each of said upper and lower straps (14) being symmetric aligned in chord direction relative to at least two pivot bearings (35, 36). Said upper and lower straps (14) are stiff in chord direction and flexible in span wise direction.

Abstract: In a rotary wing aircraft a bar (1) of composite matrix material has a longitudinal axis (8) perpendicular to a cross section with upper and lower surfaces (2, 3). At least one torsion box (17) comprises an upper and a lower layers (10, 21, 11, 22) respectively offset of a longitudinal axis (8) and of the upper and the lower surfaces (2, 3), said upper and lower layers (10, 21, 11, 22) being laterally joint, while cross sections are filled with the first group of fibers extending essentially parallel to the longitudinal axis (8).

Abstract: The invention relates to a bioreactor for cultivating phototrophic organisms in an aqueous culture medium, the reactor parts that come into contact with the culture medium being entirely or partially produced from silicone materials. The invention is characterized in that the silicone materials are produced from addition-crosslinked silicones, and the surface of the silicone materials has a contact angle to the water of at least 100°.

Abstract: The invention relates to a bioreactor for cultivating phototrophic organisms in an aqueous culture medium. The reactor parts and/or fittings that come into contact with the culture medium are entirely or partially coated with a silicone layer, and the surface of the silicone layer has a contact angle to the water of at least 100°.

Abstract: A lead lag damper (10, 11) for a helicopter rotor unit has a rotor and a hub (8), said rotor having N rotor modes, with N being the number of blades. This centered single lead lag damper (10, 11) for the entire rotor unit has an essentially cylindrical shape, with an elastomer material shear element between a first side (7) and a second side (9) having a homogenous resistance to shear deformation and being axially preloaded, so that the lead lag damper (10, 11) acts in a homogenous manner in the rotor inplane eigenmodes. Thus, the lead lag damper (10, 11) acts as a single unit on the critical inplane mode of the rotor, which is having N identical blades (1-4). The elastomeric material is loaded by a uniform shear deformation in contrary to the commonly used oscillatory deformation.

Abstract: A flexbeam unit for a multi-blade rotor of a rotary wing aircraft, said flexbeam unit defining a predetermined number of torsion elements that are connectable with associated rotor blades, at least one torsion element comprising a flexbeam element having an associated longitudinal direction and comprising inner layers of a first fiber reinforced material that are embedded between outer layers of a second fiber reinforced material, said outer layers being composed of main plies comprising unidirectional fibers and said inner layers defining a cross section profile center in said associated longitudinal direction, said cross section profile center being composed of interconnected bias plies comprising fibers that are oriented transversely relative to said unidirectional fibers.

Abstract: A flexbeam unit for a multi-blade rotor of a rotary wing aircraft, said flexbeam unit comprising a plurality of flexbeam elements that define a predetermined number of torsion elements and a ring-shaped connection zone for attachment to a rotor hub associated with a rotor shaft of said multi-blade rotor, each flexbeam element passing said ring-shaped connection zone in a tangential manner and uninterruptedly connecting a first torsion element to a second torsion element of said predetermined number of torsion elements, wherein each flexbeam element overlaps at least one in the circumferential direction of said ring-shaped connection zone immediately following flexbeam element and is overlapped by at least one in the circumferential direction of said ring-shaped connection zone immediately preceding flexbeam element.

Abstract: A flexbeam unit comprising a plurality of flexbeam elements, each defining a load passing member that is attachable to a rotor hub associated with a rotor shaft of said multi-blade rotor, said plurality of flexbeam elements defining a predetermined number of torsion elements that are connectable with associated rotor blades of said multi-blade rotor, wherein at least one of the predetermined number of torsion elements comprises at least one first flexbeam element defining a first longitudinal direction and at least one second flexbeam element defining a second longitudinal direction, wherein said at least one first and second flexbeam elements are interconnected by a beam connector in a direction transverse to said first and/or second longitudinal directions.

Abstract: A connection means (1) for mounting a rotor blade (2) to a rotor hub, particularly for mounting a rotor blade (2) to a rotor hub of a helicopter, with at least two bolts (4, 5) inserted vertically relative to a main plane of said rotor blade (2) into an end (7) of said rotor blade (2) that is generally directed towards the rotor hub. At least two bolts (4, 5) are arranged distant from each other along a longitudinal axis (6) of said rotor blade (2) to said rotor hub.

Abstract: A rotor blade (1) with an exterior shell (20) extending in a span and chord wise direction and at least one control flap (4) extending in essentially span wise direction to said exterior shell (20). Load transmission means inside said blade chamber (7) comprise piling type housings (13) respectively with one actuator (8, 9), one flap drive (10, 11) and a longitudinal girder (15). Said at least one piling type housing (13) comprises at least one upper strap (14) and at least one lower strap (14) oriented essentially in said chord direction in between said longitudinal girder (15) on the one side and the support for said at least one actuator (8, 9) on the other side, each of said upper and lower straps (14) being symmetric aligned in chord direction relative to at least two pivot bearings (35, 36). Said upper and lower straps (14) are stiff in chord direction and flexible in span wise direction.

Abstract: An aerodynamic profile (10) for aircraft, in particular for rotary wing aircraft, which profile (10) includes a cover skin (14, 15) on the pressure side and on the suction side, with a profile contour that is controllably formable in the rear profile region (13) by actuators (30), wherein each cover skin (14, 15) is designed as a non-shear-resistant sandwich that includes a film or foil (21, 22) which is connected to a non-shear-resistant core (20), wherein the cover skins (14, 15) are held in their profile shape by flexible webs (17).