A VTOL with a redundant propulsion system, the redundant propulsion system comprising two independent groups of rotors, and each group of rotors are driven by an independent engine. When any failure is detected in the first group of rotors or in its connecting parts, the second group of rotors will be accelerated to take over the first group of rotors to supply flying thrust, or vice versa. The VTOL is quiet, low cost, easy to maneuver and highly reliable, and can be used in future personal transportation.

A VTOL with a redundant propulsion system, the redundant propulsion system comprising two independent groups of rotors, and each group of rotors are driven by an independent engine. When any failure is detected in the first group of rotors or in its connecting parts, the second group of rotors will be accelerated to take over the first group of rotors to supply flying thrust, or vice versa. The VTOL is quiet, low cost, easy to maneuver and highly reliable, and can be used in future personal transportation.

A gear box includes a casing having an interior. A rotating component is arranged in the interior of the casing. A bearing including a rotating element, and a fixed element is connected with the casing in the interior. A submersible pump is arranged in the interior of the casing. The submersible pump includes a first housing portion extending about the rotating component fixedly mounted to the casing at the interior. A second housing portion is fixedly mounted to the casing at the interior and is aligned with the first housing portion. The first and second housing portions form a lubricant reservoir which holds lubricant. An impeller is mounted to the rotating component and arranged in the lubricant reservoir. One of the first and second housing portions includes an outlet through which the pumped lubricant is directed toward the rotating element.

A gear box includes a casing having an interior. A rotating component is arranged in the interior of the casing. A bearing including a rotating element, and a fixed element is connected with the casing in the interior. A submersible pump is arranged in the interior of the casing. The submersible pump includes a first housing portion extending about the rotating component fixedly mounted to the casing at the interior. A second housing portion is fixedly mounted to the casing at the interior and is aligned with the first housing portion. The first and second housing portions form a lubricant reservoir which holds lubricant. An impeller is mounted to the rotating component and arranged in the lubricant reservoir. One of the first and second housing portions includes an outlet through which the pumped lubricant is directed toward the rotating element.

A method of providing torque protection and/or thrust protection for the or each propeller of a hybrid helicopter. The hybrid helicopter includes a control system connected to the blades of each propeller and a thrust control configured to generate an order for modifying a pitch of the blades, which order is transmitted to the control system, the propeller(s) being driven in rotation by a mechanical transmission system of the hybrid helicopter. The method includes a step of having the control system keep the pitch of the blades of a propeller within at least one control envelope relating to a thrust generated by the propeller or to a torque exerted in the mechanical transmission system. In this way, the pitch of the blades of each propeller is kept between a lower limit and an upper limit of the control envelope.

An unmanned aerial vehicle includes: a vehicle main body having a first length in a first direction longer than a second length in a second direction orthogonal to the first direction; propellers that rotate in a virtual plane parallel to the first and second directions; first propeller actuation motors that are provided on the vehicle main body and respectively rotate the propellers; at least one connector that is hangable from at least one rail spaced apart from the ground surface; at least one side propeller that provides propulsion force for propelling the vehicle main body in the first direction; at least one third propeller actuation motor that is provided on the vehicle main body and rotates the at least one side propeller; and a control processor that controls the first propeller actuation motors and the at least one third propeller actuation motor.

An unmanned aerial vehicle includes: a vehicle main body having a first length in a first direction longer than a second length in a second direction orthogonal to the first direction; propellers that rotate in a virtual plane parallel to the first and second directions; first propeller actuation motors that are provided on the vehicle main body and respectively rotate the propellers; at least one connector that is hangable from at least one rail spaced apart from the ground surface; at least one side propeller that provides propulsion force for propelling the vehicle main body in the first direction; at least one third propeller actuation motor that is provided on the vehicle main body and rotates the at least one side propeller; and a control processor that controls the first propeller actuation motors and the at least one third propeller actuation motor.

A motor vehicle (100) has four centreless wheels (10) drivable for use on the ground and four propellers (16) rotatable within the open centres of the wheels (10) for use in the air. The wheel-propeller assemblies (10, 16) are carried on mounting units (14) secured to a frame (12). The mounting units (14) are rotatable on the frame (12) and the wheel-propeller assemblies (10, 16) are rotatable on their respective mounting units (14), in each case by means of servomotors, to convert the vehicle (1009) from its ground mode shown in FIG. 1 to its air mode as shown in FIG. 2, and also to turn the wheel-propeller assemblies (10, 16) so as to steer the vehicle (100) when on the ground and to tilt the wheel-propeller assemblies (10, 16) so as to direct the vehicle (100) when in the air.

A motor vehicle (100) has four centreless wheels (10) drivable for use on the ground and four propellers (16) rotatable within the open centres of the wheels (10) for use in the air. The wheel-propeller assemblies (10, 16) are carried on mounting units (14) secured to a frame (12). The mounting units (14) are rotatable on the frame (12) and the wheel-propeller assemblies (10, 16) are rotatable on their respective mounting units (14), in each case by means of servomotors, to convert the vehicle (1009) from its ground mode shown in FIG. 1 to its air mode as shown in FIG. 2, and also to turn the wheel-propeller assemblies (10, 16) so as to steer the vehicle (100) when on the ground and to tilt the wheel-propeller assemblies (10, 16) so as to direct the vehicle (100) when in the air.

A hydraulic propulsion system is disclosed which includes an input interface configured to receive mechanical power from a power source, a pressure source comprising one or more fixed or variable displacement pumps coupled to the input interface and adaptable to convert mechanical power to hydraulic power and controlling outlet pressure of the pressure source (system pressure), one or more variable displacement motors coupled to the pressure source via a corresponding high-pressure line configured to be mechanically coupled to one or more aerodynamic rotors of an aircraft and comprising a closed loop speed control arrangement in response to a commanded rotor speed, and a controller configured to control the speed of one or more variable displacement motors by providing a control signal for controlling the system pressure.