Airbus Helicopters

Debbie Leusink

David Alfano

Vincent Gareton

Guillaume Legras

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 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 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

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Aix en Provence, France

Debbie Leusink