A multirotor aircraft that includes a chassis, at least three engines that are equipped with propellers, and one or more axial free wings that are connected to the chassis by axial connections. The leading edges of the one or more axial free wings are designed to face constantly same direction when the multirotor flying, and the attack angles of the one or more axial free wings are designed to be changed relatively to the chassis due to flow of air over the one or more axial free wings.

The invention relates to a drive system for a vehicle, comprising at least one asymmetrical rotor (18), which has at least one rotor blade (20) extending radially from a rotor axle, and a counterweight (22) which is opposite the rotor axle, the system further comprising a control device for the electric motor (24), which connects the electric motor (24) to a battery for the power supply thereof, and is configured and designed, during a revolution cycle, which includes 1-3 revolutions of the rigid rotor blade (20), to bring about at least one acceleration phase, in which the electric motor (24) can be accelerated to accelerate the rotor (18), and at least one braking phase, in which the electric motor (24) can be braked, the control device being designed, during at least part of the braking phase, to connect the electric motor (24) to at least one battery element (28) in generator mode.

A self-righting aeronautical vehicle comprising a hollowed frame and a lift mechanism. The exterior of the frame and center of gravity are adapted to self-right the vehicle. The frame can include sealed, hollowed sections for use in bodies of water. The frame can be spherical in shape enabling inspection of internal surface of partially or fully enclosed structures. Inspection equipment can be integrated into the vehicle and acquired data can be stored or wirelessly communicated to a server. A controlled or other mass can be pivotally assembled to a pivot axle spanning across the interior of the frame. The pivot axis can rotate about a vertical axis (an axis perpendicular to the elongated axis). The propulsion mechanisms can be adapted for use as a terrestrial vehicle when enclosed in a sealed spherical shell.

Off-board gyrocopter take-off systems and associated methods are disclosed. A representative method includes restraining a gyrocopter from vertical and lateral movement, pre-rotating a fixed-pitch lift rotor of the gyrocopter via a power source located off the gyrocopter, and releasing the gyrocopter for vertical movement to allow the gyrocopter to lift under a force provided by the lift rotor. Optionally, the method can further include interrupting or reducing power from the power source to the gyrocopter as a way to release the gyrocopter for vertical movement.

Off-board gyrocopter take-off systems and associated methods are disclosed. A representative method includes restraining a gyrocopter from vertical and lateral movement, pre-rotating a fixed-pitch lift rotor of the gyrocopter via a power source located off the gyrocopter, and releasing the gyrocopter for vertical movement to allow the gyrocopter to lift under a force provided by the lift rotor. Optionally, the method can further include interrupting or reducing power from the power source to the gyrocopter as a way to release the gyrocopter for vertical movement.

A method for equalizing rolling moments at high advance ratios is disclosed including impelling an aircraft in a forward direction at an airspeed by means of a thrust source and rotating a rotor of the aircraft at an angular velocity with respect to the airspeed effective to cause a positive total lift on each blade due to air flow over the blades in the retreating direction when the blade is moving in the retreating direction. The rotor includes an even number of blades placed at equal angular intervals around the rotor hub. One or both of cyclic pitch and rotor angle of attack are adjusted such that a rolling moment of the retreating blade due to reverse air flow is between 0.3 and 0.7 times a rolling moment on the advancing blade due to lift.

A method for equalizing rolling moments at high advance ratios is disclosed including impelling an aircraft in a forward direction at an airspeed by means of a thrust source and rotating a rotor of the aircraft at an angular velocity with respect to the airspeed effective to cause a positive total lift on each blade due to air flow over the blades in the retreating direction when the blade is moving in the retreating direction. The rotor includes an even number of blades placed at equal angular intervals around the rotor hub. One or both of cyclic pitch and rotor angle of attack are adjusted such that a rolling moment of the retreating blade due to reverse air flow is between 0.3 and 0.7 times a rolling moment on the advancing blade due to lift.

A rotatable thruster aircraft includes a fixed wing; rotatable thruster assemblies, each including first and second thrusters that provide rotation via differential thrust; and vertical lift thrusters, optionally connected via an elongated member; and an aircraft control unit, including a processor, a non-transitory memory, an input/output component, and a power manager that controls specific power applied to the thrusters.

A rotatable thruster aircraft includes a fixed wing; rotatable thruster assemblies, each including first and second thrusters that provide rotation via differential thrust; and vertical lift thrusters, optionally connected via an elongated member; and an aircraft control unit, including a processor, a non-transitory memory, an input/output component, and a power manager that controls specific power applied to the thrusters.

Embodiments of the invention are directed to systems and methods for reducing drag on an aircraft. The aircraft can include at least one propulsion system with rotor blades configured to reduce aerodynamic drag when the propulsion system is deactivated. To reduce the amount of drag, the rotor blades can be locked into an aerodynamic position, and prevented from passively spinning. Additionally, the rotor blades can be configured to have angular positions that reduce drag. For example, the rotor blades as a group may be configured to generally point toward and/or away from an airflow current.