Abstract: An anti-torque system (10) for a helicopter (1) is described that comprises: an electric power supply unit (15); at least one first rotor (17), operatively connected to an electric power supply unit (15) and operable by the electric power supply unit (15) so as to rotate with a first variable angular speed; and at least one second rotor (25) operatively connected to electric power supply unit (15) and operable by the electric power supply unit (15) so as to rotate with a second variable angular speed.

Abstract: A rotor for an aircraft is described having: a support angularly fixed with respect to an axis and housing a power source; a unit rotatable about axis and housing an electrical load of the resistive type; and a power supply system for the electrical load and comprising: a first transformer electrically interposed between the power source and the load; the first transformer comprises: a first winding arranged on the support and a second winding arranged on the unit, a stator carried by the support, rotationally fixed with respect to axis and to which the first winding is fixed; and a rotor operatively connected to the unit and to which the second winding is fixed; the power supply system comprises a capacitive circuit electrically connected to the first transformer, so as to reduce the reactive power absorbed by the rotary transformer.

Abstract: There is disclosed a rotor for an aircraft capable of hovering, comprising: a stator; a rotatable element, which is rotatable about an axis with respect to stator; a blade, which is connected with element; a support element, which supports a source of a magnetic field and is either stationary or driven in rotation at a first rotational speed; and a first electric circuit, which is angularly integral with element and can be driven in rotation at a second rotational speed different from first rotational speed; first electric circuit being electromagnetically coupled with source so that an electromotive force is magnetically induced in first electric circuit and an first electric current flows in first electric circuit; rotor further comprises a second electric circuit which is either stationary or driven in rotation at a first rotational speed, and a sensor generating a signal associated to a back electromotive force induced on second electric circuit.

Abstract: A rotor for an aircraft capable of hovering includes a stationary support structure and a rotative element, which is rotatable about a first axis with respect to said stationary support structure with a first rotational speed. The rotor includes at least one blade, which is operatively connected with said rotative element; and a transmission group, which includes an output element rotatable about first axis with a second rotational speed different from first rotational speed.

Abstract: A rotor for an aircraft capable of hovering includes a stationary support structure and a rotative element which is rotatable about an axis with respect to the stationary support structure. The rotor has at least one blade, which is operatively connected with a rotative element. The rotor has a source of a magnetic field, which is either stationary or driven in rotation at a first rotational speed and an electric conductive element, which is operatively connected to the rotative element and can be driven in rotation at a second rotational speed different from first rotational speed. An electric conductive element is electromagnetically coupled so that an electromotive force is magnetically induced in electric conductive element itself Two rings extend radially inward from a tubular body of the rotor hub with the first ring connected to a plurality of thermally conductive rings of a flow deflector at an axial end of the rotor and the second ring supports the electric conductive element.

Abstract: An anti-torque system (10) for a helicopter (1) is described that comprises: an electric power supply unit (15); at least one first rotor (17), operatively connected to an electric power supply unit (15) and operable by the electric power supply unit (15) so as to rotate with a first variable angular speed; and at least one second rotor (25) operatively connected to electric power supply unit (15) and operable by the electric power supply unit (15) so as to rotate with a second variable angular speed.

Abstract: There is disclosed a rotor for an aircraft capable of hovering, comprising a stationary support structured; a rotative element, which is rotatable about an axis with respect to stationary support structure; at least one blade, which is operatively connected with rotative element; a source of a magnetic field, which is either stationary or driven in rotation at a first rotational speed; and an electric conductive element, which is operatively connected to rotative element and can be driven in rotation at a second rotational speed from first rotational speed; electric conductive element is electromagnetically coupled with source, so that an electromotive force is magnetically induced in electric conductive element itself, wherein two rings extend radially inward from a tubular body of the rotor hub, the first ring connecting to a plurality of thermally conductive rings of a flow deflector at an axial end of the rotor, the second ring supporting the electric conductive element.

Abstract: There is disclosed a rotor for an aircraft capable of hovering, comprising: a stationary support structure; a rotative element, which is rotatable about a first axis with respect to said stationary support structure with a first rotational speed; at least one blade, which is operatively connected with said rotative element; and a transmission group, which comprises an output element rotatable about first axis with a second rotational speed different from first rotational speed.

Abstract: There is disclosed a rotor for an aircraft capable of hovering, comprising: a stator; a rotatable element, which is rotatable about an axis with respect to stator; a blade, which is connected with element; a support element, which supports a source of a magnetic field and is either stationary or driven in rotation at a first rotational speed; and a first electric circuit, which is angularly integral with element and can be driven in rotation at a second rotational speed different from first rotational speed; first electric circuit being electromagnetically coupled with source so that an electromotive force is magnetically induced in first electric circuit and an first electric current flows in first electric circuit; rotor further comprises a second electric circuit which is either stationary or driven in rotation at a first rotational speed, and a sensor generating a signal associated to a back electromotive force induced on second electric circuit.

Abstract: An aircraft capable of hovering, and characterized by having at least one sensor, which has a plane sweep region and is designed to acquire, when the aircraft is maneuvering, values of respective distances between first points on an obstacle within the plane sweep region, and a second point on the aircraft; and a control unit designed to generate an alarm signal when at least one of the first points lies within a safety region containing the second point on the aircraft.

Abstract: An aircraft, capable of hovering, having drive means; and at least one exhaust duct connected to an outlet of the drive means to expel the exhaust gas, produced by fuel combustion, from the aircraft. At least part of the exhaust duct has a thermoelectric conversion circuit for Seebeck-effect converting to electric energy the thermal gradient produced between the inside and outside of the exhaust duct by flow of the exhaust gas.

Abstract: An aircraft, capable of hovering, having drive means; and at least one exhaust duct connected to an outlet of the drive means to expel the exhaust gas, produced by fuel combustion, from the aircraft. At least part of the exhaust duct has a thermoelectric conversion circuit for Seebeck-effect converting to electric energy the thermal gradient produced between the inside and outside of the exhaust duct by flow of the exhaust gas.

Abstract: An aircraft capable of hovering, and characterized by having at least one sensor, which has a plane sweep region and is designed to acquire, when the aircraft is manoeuvring, values of respective distances between first points on an obstacle within the plane sweep region, and a second point on the aircraft; and a control unit designed to generate an alarm signal when at least one of the first points lies within a safety region containing the second point on the aircraft.

Abstract: The organ transplants are intended to be used as a replacement (prostheses) for organs or parts of organs, for examples arteries or veins, which have undergone pathological change or are functionally impaired. The organs, which are taken from a fish, bird or higher mammal, are subjected to crosslinking of the amino groups and of the alcoholic hydroxyl groups of the peptide chains of the intercellular matix by means of a di-, tri- or poly-carboxylic acid. It is advantageous subsequently to treat the crosslinked product with a dialdehyde, in order to bind amino groups which have not reacted, or to free the crosslinked product from material which potentially may act as an antigen, by hydrolysis with ficin, papain or a protease having a smaller action. After the hydrolysis, a comprehensive crosslinking is appropriately ensured using a dialdehyde or a di-, tri- or poly-carboxylic acid.