In an embodiment, a rotorcraft includes an airframe; a main rotor transmission; one or more brackets mounting the main rotor transmission to the airframe, longitudinal axes of the one or more brackets being substantially parallel with a longitudinal axis of the rotorcraft; and one or more restraints mounting the main rotor transmission to the airframe, the one or more restraints being mounted at an angle non-orthogonal to the longitudinal axis of the rotorcraft and a lateral axis of the rotorcraft.

In some examples, an oscillatory pumping system comprises: one or more active piston, a fluid, and two motors. The one or more active piston is disposed in a channel fluidically coupling two fluid chambers. The passive piston has a frequency response operable to counteract a vibratory displacement. The fluid is disposed in the channel and the two fluid chambers. The two motors couple to the one or more active piston. The two motors are operable to selectively change the frequency response of the passive piston based on oscillating the one or more active piston.

A rotor for a hover-capable aircraft is described, comprising: a hub rotatable about an axis and, in turn, comprising a plurality of blades; a mast connectable to a drive member of the aircraft and operatively connected to the hub to drive the hub in rotation about the axis; and damping means for damping vibrations transmitted to the mast, which comprise a mass designed to oscillate in a plane transversal to the axis so as to contain flexural vibrations of the mast generated by rotation of the blades; the damping means also comprise elastic means having a desired stiffness along the axis and operatively connected to the mass to contain vibration of the mast along the axis.

A rotor-regulation system includes a rotor comprising a plurality of blades, a mechanically driven hydraulic pump, a rotor drive shaft operable to drive the rotor and the mechanically driven hydraulic pump, and a throttling valve coupled to the mechanically driven hydraulic pump and operable to modulate rotation of the rotor.

According to certain aspects of the disclosure, a computer-implemented method may be used for rotorcraft track and balance. The method may include capturing one or more images of at least one rotating blades of a rotorcraft and analyzing the one or more images of the at least one rotating blades to determine blade information. Additionally, the method may include determining a location of the at least one rotating blades in the one or more images based on the blade information and calculating blade position information based on the determined location of the at least one rotating blade and a parameter of a user device capturing the one or more images. Additionally, the method may include displaying the blade position information to the user device and displaying instructions on one or more adjustments to the at least one rotating blades of the rotorcraft based on the blade position information.

A device for detecting the approach of a vortex ring state for a rotary wing aerodyne, the detection device including a set of vibration sensors configured to be distributed in or on the aerodyne, and a data processing unit configured to receive in real time measurement data from the sensors, process the data in order to calculate in real time the vibration spectrum of the aerodyne, detect in real time, by vibration analysis, the approach of a vortex ring state as a function of the calculated vibration spectrum, and issue an alarm in the event of detection of the approach of a vortex ring state.

Systems, devices, and methods for stopping the rotation of propellers used in unmanned aerial vehicles (UAV) such as drones are disclosed. The propellers are stopped in response to detecting when beams of light adjacent the propellers are blocked.

An aircraft is described comprising a transmission unit with a first module and a lubrication system; the first module comprises a casing and a movable member; the lubrication system comprises a header, a nozzle fed with the lubricating fluid and designed to feed the lubricating fluid inside the casing of the first module, a collection tank for the lubricating fluid injected by the nozzle, and recirculation means designed to cause the recirculation of the lubricating fluid from the collection tank to the feed header; the first module comprises a valve available in a first configuration, in which it enables the outflow of said lubricating fluid from said module to the recirculation means when the pressure of the lubricating fluid inside the header is greater than a threshold value; and in a second configuration, in which it fluidically isolates the module from the recirculation means when the pressure of the lubricating fluid inside the header is less than the threshold value.

A strut assembly for a vibration isolation device is disclosed, comprising a piston spindle; a first elastomeric member and a second elastomeric member bonded to the piston spindle and in contact with an upper housing and a lower housing, respectively; a first strut support and a second strut support attached to or integral with the upper housing and the lower housing, respectively; a first strut spindle and the second strut support configured to be placed in the first strut support and the second strut support, respectively; and one or more removable struts configured to be engaged to the first strut spindle and to the second strut spindle, wherein at least one of the first or second strut spindles is removable such that the one or more struts can be replaced without breaking a bonding of the first elastomeric member, the second elastomeric member, or both.

A high-place observation device for stably performing a fixed-point observation of a target object from a high place is provided. The high-place observation device provides a long pole which is formed to extend and contract freely and which stands on the installation surface, a rotorcraft for positioning the pole to a desirable height position by extending and contracting the pole by a floating force in a connected state, a winding mechanism which fixes and maintains the height position of the pole to the height position set by the rotorcraft, and a camera attached to the rotorcraft.