Abstract: The invention relates to improvements with regards to the control of VTOL aircraft that use two propellers or fans as the primary lifting devices in hover. More particularly, the invention is a means for effecting control of the aircraft using just the two propellers alone, and comprises the in-flight tilting of them—which are of the conventional, non-articulated type (though they may have collective blade-pitch)—directly and equally towards or away from one another (and therefore about parallel axes) as necessary for the generation of propeller torque-induced and gyroscopic control moments on the aircraft about an axis perpendicular to the propeller tilt and mean-spin-axes. For a side-by-side propeller arrangement, therefore, their (lateral) tilting towards or away from one another produces aircraft pitch control moments for full control of the aircraft in that direction.

Abstract: A tilting rotor of a convertible aircraft comprises, between the mast and the hub, a constant velocity drive mechanism and pivoting arrangement comprising two gimbals, each of which is driven by the mast and pivots about one respectively of two diametral axes by two diametrically opposite bearings. Each gimbal is also hinged to the hub by ball joint connections diametrically opposite and centred respectively in a radial plane passing through the axis of the mast and through the diametral axis about which the other gimbal pivots. The two resulting trains transmitting torque between the mast and the hub have substantially the same torsional rigidity, and one at least of the components of each torque transmission train exhibits a flexibility in deformation about the axis of rotation of the hub.

Abstract: A device for lubricating a power gearbox having a variable orientation and a closed space has a lubricating unit that supplies lubricant to at least one element of the gearbox, which needs to be lubricated. A collecting reservoir collects lubricant from the closed space. A drain screw chamber, within the closed space, has a number of orifices disposed between different zones of the closed space and the drain screw chamber for passing lubricant there between. At least one rotary drain screw, which is produced in the form of an Archimedean screw, is disposed in the drain screw chamber to convey the lubricant from the drain screw chamber to the collecting reservoir. A drive unit drives the drain screw in rotation for conveying the lubricant. The orifices open respectively different zones of the closed space to the drain screw chamber such that the drain screw chamber can always collect lubricant from the different zones regardless of the orientation of the gearbox.

Abstract: A preferred embodiment of a rotary-wing aircraft comprises a fuselage, a tail boom fixedly coupled the fuselage, a pylon fixedly coupled to the tail boom, and a main rotor assembly rotatably coupled to the fuselage and comprising a hub and a plurality of rotor blades pivotally coupled to the hub. The preferred embodiment also comprises a cyclic control adapted to vary an orientation of the rotor blades in relation to the hub on a cyclical basis, and a horizontal stabilizer mounted on one of the pylon and the tail boom. At least a portion of the horizontal stabilizer is movable in relation to the one of the pylon and the tail boom and a position of the at least a portion of the horizontal stabilizer is controllable independent of the cyclic control.

Abstract: A drag damper for use on a rotary wing aircraft rotor comprises a body defining two variable volume chambers linked by a piston. The chambers are filled with fluid and are connected by a restriction port (35) and by a channel (32) of larger cross-section than the restriction port. A secondary piston slidable and pressure-tight piston is fitted in the channel and loaded by an elastic bias (34). The equivalent mass of this secondary piston (33) and of the fluid which it displaces, and the stiffness of the elastic bias (34) are such that the secondary piston is resonant in the channel (32) at the rotation frequency of the rotor, to filter the dynamic component at this frequency of stresses applied to the damper (20).

Abstract: The present invention relates to a single-blade main rotor for helicopters designed so that the component of the blade lift normal to the rotational axis of the rotor is compensated by the inertial force obtained through the self-adjustment of the position of the rotor centre of mass relative to its rotation axis, it being provided that the position of the rotor centre of mass is determined by the coning angle of the blade.

Abstract: The subject tiltrotor aircraft has three modes of operation: airplane mode, helicopter mode, and transition mode. A tilting mast, which transitions the aircraft between airplane mode and helicopter mode, is controlled by systems that allow selective movement of the rotor blades between the flight modes. A hub couples the rotor blades to the tilting mast such that torque and thrust are transferred, while allowing rotor thrust vector tilting. A main swash plate controls rotor thrust vector direction. Pitch horns are coupled to the rotor blades and the main swash plate via pitch links such that swash plate inputs are communicated to the rotor blades. The pitch links are coupled at “delta-3” values that are not optimum. A feedback swash plate and feedback links receive disk tilting inputs from the rotor blades, and supply inputs to the main swash plate, which compensates for the less than optimum delta-3 coupling.

Abstract: An arrangement for a horizontally and vertically flying aircraft of the type that for vertical flight has rotors that form a lifting area such as in a helicopter, and where the rotors are retracted within a rotor disc (4) during horizontal flight. The rotors (8) are supported with fixed pitch in the rotor disc (4). The centre point of the lifting area is arranged to be capable of being shifted in an xy plane, or means are provided to be brought at determined points within the lifting area of the rotor disc (4) to break the lifting capabilities in the effective rotor disc for manoeuvring and counteracting differential lift during propulsion of the aircraft in vertical flight and on the transition from vertical to horizontal flight.

Abstract: An aircraft has a fuselage designed essentially as an aerostatic lift body and combined lift and propulsion devices which are articulated on the fuselage, are provided with propellers and form propulsion units and which in each case are tiltable between a lift position, in which the respective propeller rotation plane is essentially horizontal and the output shaft of the associated drive, said output shaft acting on the respective propeller shaft, is essentially vertical, and a propulsion position, in which the respective propeller rotation plane is essentially vertical and the output shaft of the associated drive, said output shaft acting on the respective propeller shaft, is essentially horizontal. The propeller rotation plane has all-round inclinability relative to the output shaft of the associated drive, said output shaft acting on the propeller shaft.

Abstract: The present invention concerns a vertical takeoff and landing aircraft (VTOL) with multiple rotors which can immediately change pitch angle of each rotor to stabilize body balance when cargo or person is picked up or taken off.

Abstract: A rotor aircraft has an adjusting mechanism that controls the sensitivity of the control stick relative to fore and aft tilt of the rotor. The control stick is pivotable between fore and aft directions as well as laterally about a control stick pivot point. A rotor linkage is connected between the control stick and the rotor rotor head. The rotor linkage assembly tilts the rotor head in response to tilting movement of the control stick. The linkage assembly has a control point that rotates at a radius about the control stick pivot point. An adjusting member located between the control stick and the linkage assembly can be moved to change the radius of the control point to the control stick pivot point. The change in radius corresponds to the amount of tilt that the rotor head make while the control stick moves between full aft and full forward positions. The control stick also controls ailerons and a horizontal stabilizer but these control services are not affected by the adjusting member.

Abstract: A rotor for rotary wing aircraft includes a number of features that reduce the collective forces required to control the pitch of the rotor. The spar caps of the spar become joined to one another at the same point where bonding begins between the blade and the spar. The tendency of blade to want to flatten out is minimized since the centrifugal force acting on the spar is located at or near the pitch change axis. Tip weights are located at or near the pitch change axis as well. In a preferred embodiment, the tip weights are located evenly in front of and behind the structural center of the inboard section of the spar. The blade of the rotor and the tip are not swept back.

Abstract: A cyclic and collective pitch control device for a helicopter rotor, fitted about a fixed casing having an axis, and having a substantially sleeve-shaped movable element fitted in axially-sliding manner to the casing; a rocking-plate assembly fitted coaxially to the movable element so as to rock in any direction with respect to the movable element, and in turn having an angularly-fixed first annular element, and a second annular element rotating on the first annular element together with a drive shaft of the rotor fitted through the casing; supporting and actuating means cooperating with the first annular element to move the assembly and the movable element jointly along the axis with respect to the casing, and to rock the assembly with respect to the movable element; and prismatic connecting means between the movable element and the casing to prevent angular displacement of the movable element with respect to the casing.

Abstract: A one-man helicopter 1 in which a drive transmission 10 that transmits driving force to upper and lower rotors 5 and 6 comprises first and second planet gear mechanisms 100 and 200 provided with a common carrier 104. When the common carrier 104 is rotated by a motor 301, a differential motion is generated between the two planet gear mechanisms. This results in the rotors being rotated at different velocities, which can be used to control yaw. A fore-and-aft swing mechanism 400 and right-and-left swing mechanism 500 depend from the lower end of a vertical shaft 41 on which the rotors are supported. Moving a stick 8 forward or backward, or to either side, tilts the vertical shaft 41 in the same direction. When the stick 8 is not subjected to a controlling force, the vertical shaft 41 reverts automatically to its original vertical state. This configuration makes it possible to realize a coaxial twin-rotor type helicopter having a compact, structurally simple control mechanism.

Abstract: The device for the individual control of the blades includes at least two sets of rotating swashplates centered on the rotor axis and non-rotating swashplates at least inclinable in all directions under the action of at least two actuators inserted between the first set and a non-rotating structure, and under the action of at least one other actuator inserted between this structure and the second set. Each non-rotating plate is held by a connecting piece to the non-rotating structure, and each rotating plate is rotated with the rotor and connected to at least one blade respectively of the rotor via a respective pitch rod. The device also includes at least as many actuators as the rotor has blades, and all the actuators are non-rotating.

Abstract: In the case of a helicopter comprising a rotor system (3) with rotor blades (6 and 6′) held on a fuselage (2) and at least one rotor shaft (5 and 5′) and furthermore comprising a drive system (4) for causing rotation of the rotor system (3), the rotor system (3) together with the drive system (4) is able to be slid in the longitudinal direction of the fuselage (2) and to be pivoted around a pivot axis extending along the fuselage (2).

Abstract: The present invention comprises an apparatus for locking the pitch axes of the rotor blades of a rotor/wing aircraft so as to form a rigid wing. In one embodiment of the present invention the rotor blades of a rotor/wing aircraft are locked to each other to form a rigid wing assembly having a common pitch axis. This wing assembly is then locked in position about its pitch axis by means of a pitch lock apparatus that engages the lower end of the pitch link of the rotor blade that is oriented at the leading edge of the fixed wing. In another embodiment each rotor is independently locked about its respective pitch axis by means of two separate pitch lock apparatus. By locking the rotor blades into a rigid assembly by means of an independent rigid pitch lock apparatus, it is possible to provide a rotor/wing aircraft having a fixed wing with more predictable and controllable response to aerodynamic forces.