Airbus Helicopters

David Alfano

Damien Desvigne

Debbie Leusink

Raphael Fukari

Guillaume Legras

Vincent Gareton

Jean Nicola

Raphaël Fukari

A sleeve connecting a blade to the hub of a rotor of a rotary wing aircraft. The sleeve has a leading edge and a trailing edge, together with a protuberance arranged on the trailing edge. The dimensions of the protuberance are linked to the dimensions of the sleeve. The presence of the protuberance serves to improve the aerodynamic behavior of the sleeve and of the rotor during rotation of the rotor while the aircraft is moving forwards, both when the sleeve is advancing and when it is retreating. The presence of the protuberance also serves to reduce the vibration generated by a wake of the rotor on a tail boom or on a horizontal and/or vertical stabilizer of the aircraft.

Aircraft rotor blade sleeve having a protuberance in its rear zone, and a rotor provided with such a sleeve

A tail boom having a structure and a protuberance, the protuberance being secure with the structure. In each section of the tail boom, the protuberance extends in elevation over an extension height (Hext) and it extends laterally over an extension thickness (EPext), the extension height (Hext) lying in the range 0.05 times the maximum thickness (EPmax) of the structure, included, to 0.5 times the maximum thickness (EPmax), included, of the section, the extension thickness (EPext) lying in the range 0 to 0.4 times the maximum thickness (EPmax), included, of the section.

Rotorcraft tail boom, and a rotorcraft

A thick airfoil shape that is to form a blade neck for blades, the blade neck connecting a blade root to a streamlined portion of the blade, and/or a blade cuff connecting a blade to the hub of an aircraft rotor. The thick airfoil shape has a leading edge and a trailing edge together with thick airfoil profiles for which the particular positions of points defining the maximum thickness of each airfoil profile make it possible to improve the aerodynamic behavior of the thick airfoil shapes and of the rotor during rotation of the rotor while the aircraft is advancing, for the blade both when it is advancing and when it is retreating. The thick airfoil shape also serves to reduce the vibration as generated by a wake from the rotor on a tail boom or a horizontal and/or vertical stabilizer of the aircraft.

Thick airfoil shapes for blade necks and for blade cuff fairings for an aircraft rotor

A method of optimizing sections of a tail boom for a rotary wing aircraft, and also to a tail boom including such sections. The method comprises the step of creating a database characterizing standard sections for a tail boom that give precedence to minimizing a negative lift and/or to increasing a lateral force generated by the air stream from the main rotor of the aircraft flowing over the tail boom, a step of establishing looked-for aerodynamic and structural characteristics for said tail boom, and a step of defining the sections of the tail boom as a function of the standard sections and of the looked-for aerodynamic and structural characteristics. The tail boom as defined in this way optimizes the reduction in the negative lift and/or the increase in the lateral force generated by the air stream from the main rotor.

Method of optimizing sections of a tail boom for a rotary wing aircraft

A head for a rotor of a rotorcraft, the head comprising a cap extending radially from an axis of rotation in elevation towards a periphery and extending in azimuth over 360 degrees, the cap extending in thickness between an inside face that is to face a hub of the rotor and an outside face overlying the inside face, the periphery being crenellated to define a succession of crenellations and of notches, each notch allowing a blade of the rotor to perform flapping motion.

Rotor head, a rotor, and a rotorcraft

A blade of a rotor for a rotary wing aircraft. The blade presents relationships for variation in the sweep and in the chord of the profiles of sections of the blade, in particular in order to improve the twisting stiffness and the bending stiffness of the blade. The blade is then double-tapered and it presents three sweeps, making it possible firstly to improve the aerodynamic performance of the blade in forward flight, and secondly to reduce the noise given off by the blade, in particular during an approach flight.

Aircraft rotor blade of shape adapted for acoustic improvement during an approach flight and for improving performance in forward flight

A blade of a rotor for a rotary wing aircraft. The blade presents a combination of relationships for variation in the sweep, the chord, and the twist of the airfoil profiles of the sections of the blade in order, firstly to improve the aerodynamic performance of the blade both in forward flight and in stationary flight, and secondly to reduce the noise given off during approach flight. The blade is double-tapered and presents three sweeps. The twist relationship is substantially constant over a first portion of the blade, and then decreases over the remainder of the blade in linear or in non-linear manner. Suitable variation in the gradient of the twist of the blade makes it possible to improve the aerodynamic performance of the blade in forward flight and in hovering flight.

Aircraft rotor blade of shape adapted for acoustic improvement during approach flights and for improving performance in hovering flight and in forward flight

A dome for a rotor comprising a cap extending radially from an axis of rotation in elevation towards a periphery and in azimuth over 360 degrees, the cap extending in thickness from a bottom face towards a top face above the bottom face. The dome includes at least one slot extending between the periphery and the axis of rotation in elevation, each slot passing right through a thickness of the cap by extending in elevation from the bottom face to the top face.

Rotor dome, a rotor, and a rotorcraft

A dome for a rotor of a rotorcraft, the dome comprising a cap extending radially from an axis of rotation in elevation towards a periphery and in azimuth over 360 degrees, the cap extending in thickness from a bottom face for facing a hub of the rotor towards a top face above the bottom face. At least one of the top and bottom faces is an undulating face that undulates at least in azimuth between the periphery and the axis of rotation in elevation, by including in azimuth along at least one internal circle a succession of bulges and of recesses.

An aircraft having a sponson extending substantially transversely relative to a main body of the fuselage of the aircraft and substantially perpendicularly relative to a vertical anteroposterior plane of symmetry P of the main body of the fuselage when the aircraft is standing on a horizontal support, the sponson including a notch locally reducing a cross-section of the sponson in a connection zone of the sponson, the connection zone being suitable for being arranged in the immediate proximity of the main body of the fuselage of the aircraft from which the sponson emerges transversely, the notch being open at least to a front outside face and to a top outside face of the sponson and being suitable for receiving a bottom portion of a sliding side door when in its open position.

Aircraft including a fuselage sponson

A rotorcraft provided on top with a waterdrop-shaped fairing arranged below the rotary wing of a main rotor of the rotorcraft and overlying a cover covering a power plant of the rotorcraft. The trailing edge(s) of the fairing is/are provided with a respective movable member guiding a first stream of air flowing along the fairing and escaping from the trailing edge towards the rear of the rotorcraft in flight. By way of example, the movable member is arranged as a flap or as a bladed roller that may potentially be motor-driven as a function of the effects of the first stream of air on the behavior of the rotorcraft in flight.

Rotorcraft top fairing fitted with a movable member for guiding a stream of air flowing towards the rear of the rotorcraft

A rotorcraft provided on top with a fairing () arranged below the rotary wing of a main rotor of substantially vertical axis of the rotorcraft, and covering a mechanism enabling the blades of the rotary wing of the main rotor to be operated. The streamlined shape of the fairing () is shaped longitudinally like a drop of water that is truncated in its rear portion. The truncated portion () of the waterdrop-shaped profile of the fairing () forms the rear wall of the fairing () and is provided with a transversely middle hump (). Said hump () is provided with projections in relief () arranged as waves in a longitudinal succession extending along the side walls of the fairing (), and the truncated portion () is arranged in a plane sloping towards the rear of the rotorcraft.

Rotorcraft top fairing having a profile in the shape of a truncated drop of water that is provided with a hump of uneven surface

A fairing () for a structural element of a rotorcraft, the fairing including a rear portion () that is substantially orthogonal to the longitudinal direction (L) of the aircraft, extending between two spaced-apart trailing edges () and thus presenting a determined width, said rear portion () closing at least part of the internal volume defined by the fairing () and generating aerodynamic drag in forward flight. According to the invention, the rear portion presents, at least at the trailing edges (), a shape that is perturbed on the streamlines () of the air-flow.

Growing community of inventors

Aix en Provence, France

David Alfano