helicopter rotor blade manufacturing process

The spar core is first prepared by polymerizing together cores which are made of an expanded material and which are separated by glass fabric partitions. ... Each blade is put in motion by an electric motor mounted on it which swings a weight up and down. In a preferred embodiment of the blade according to this invention, the D-shaped spar, the solid core and the sheet like member form a strengthening frame-work extending along the chord of the blade cross-section over about the front half thereof so as to form substantially the whole front half part of the blade. ATI designed, analyzed, and tested composite main-rotor blades to replace the metal blades on Carson Helicopter's S-61 (H-3). Also, these very high elasticity modulus fibres call for a manufacture which is not only more difficult but also costlier, since fabrics produced with such fibres are difficult to coat and to stick, because they have incompatibility with some resins, and their stiffness makes it difficult to position them. Control rods from the upper swash plate have a connection point on the blades, making it possible t… The rear filling element 3, which engages completely with the rear surface 10 of the torque-tube 8, is formed in its bottom front part with a recess 11 which is filled very accurately by the overlapping part 9. the huge loading and the harmful consequences of the weather reduce the life-time of the helicopter rotor blades. 76.08109 (2,304,512) to Textron Inc., published on Oct. 15, 1976, discloses a composite rotor blade, comprising a substantially C-shaped two-part leading edge member consisting of plastics strengthened by longitudinal fibres, an inner tubular sleeve consisting of plastics strengthened by fibres arranged in layers crossing each other, said inner sleeve being engaged into the rear open channel of said C-shaped leading edge member, an outer tube consisting of plastics strengthened by fibres arranged in layers, crossing each other, said outer tube surrounding said leading edge member and said inner sleeve, a rear member, and a covering jointing together said outer tube and said rear member. Moreover, its mechanical strength is reduced and its manufacturing is made uneasy because the C-shaped leading edge member has a rear open channel, into which the inner sleeve is to be engaged, so that said C-shaped leading edge member is necessarily a two-part member. The aerodynamic module is implemented for rotor blade performance analysis where the rotor blade planform and the airfoil are considered at the same time. Together, the projectors and software simplify and accelerate manual composite layup processes. The blade is prepared in a metal mould consisting of two rigid partial moulds--a top partial mould 14 and a bottom partial mould 15. towards the blade trailing edge--to form an overlapping part 9 adapted to receive shear forces in this zone of the blade. Each main rotor blade is an aero foil section, which produces lift. Many different kinds of rotor blade, specially for helicopter rotors, are known which are made of plastics strengthened by high-strength synthetic fibres. A rotor blade, specially for a helicopter rotor, which blade is made of reinforced plastics and a process for making this blade in a single molding operation. 2 is a part sectional view in oblique perspective of the root part of the blade of FIG. Our state-of-the-art facilities are fully equipped and staffed to meet a wide range of manufacturing requirements. Here we provide some background information on the design. After installation on the helicopter, the dynamic balancing of the rotor blades is carried out to bring vibrations within a set limit. This blade comprises: a solid one-piece leading edge spar embodied by strands of glass fibre filaments extending lengthwise over the whole length of the blade; a core made of a lightweight cellular substance and placed contiguous with the spar rear face; a thick sheet-like member extending around the spar and the core and comprising at least one layer of a fabric consisting of parallel glass fibres disposed askew of the blade longitudinal axis so as to form a torque-tube; a rear filling element, and a covering extending around the torque-tube and the rear filling element. These vibrations have an almost constant frequency due to the constant speed of rotating parts. The upper swash plate connects to the mast, or rotor shaft, through special linkages. No. OBJECTIVE / SOLUTION. 3,321,019 to Dmitroff and Fox, issued on May 23, 1967, also discloses the manufacturing of a glass fibre reinforced plastics blade. The top partial mould 14, in which the upper-surface skin of the covering 4 has been placed, is then positioned on and locked to the bottom partial mould 15. 1, 1966, also discloses a plastics blade comprising a core, a spar assembly and a leading-edge assembly, which is prepared beforehand, and then assembled together with the blade covering, consisting of sheets or the like of reinforced plastics. Balancing a Helicopter Rotor Blade is most commonly only thought of as being the Dynamic Blade balancing component of the complete Balancing Process. Propeller blade with lightweight insert and bulkheads. The skeins or the like then extend back from the socket-like members 6 to the blade tip. A second object of this invention is to design a rotor blade which can be produced in a single mould in which all the components of the blade are assembled, then submitted to a single operation for polymerizing the substances impregnating said components, so as to provide a simple, lightweight and low-cost rotor blade. 4 is a cross sectional view through line IV--IV of FIG. The framework 2 and element 3 are enveloped or encased completely by the covering 4, which is embodied by pre-impregnated glass fibre fabrics the edges of which are jointed in a horizontal plane at the back of the blade so as to form a trailing-edge 12. French Pat. Also, these very high elasticity modulus fibres call for a manufacture which is not only more difficult but also costlier, since fabrics produced with such fibres are difficult to coat and to stick, because they have incompatibility with some resins, and their stiffness makes it difficult to position them. The safe life testing of rotary wing aircraft is of paramount importance and especially as it applies to the rotor blades. On 7 April 2016 Leonardo Helicopters AW139 N639NA, operated by Chevron USA as a Part 91 ‘business flight’ sustained damage to a Main Rotor Blade (MRB) tip while flying over the Gulf of Mexico. RTB equipment hardware and software has all but plateaued in development. The blade design incorporates an advanced aerodynamic shape with double 3 is a view in oblique perspective of the blade of FIGS. No. Helicopter main rotor blades are experiencing unacceptable removal rates due to erosion from sand and moisture. 3M Report, “ Wet Application Instructions-Draft- For Helicopter Blades 2. Helicopter Rotor Blade 3 Structural Loading of a Rotor Blade The rotor blades of a helicopter are airfoils that provide aerodynamic forces when exposed to a relative motion of air across their surface. In the case of fatigue- ... blade manufacturing in a two-section metal die (Figure 7), and (4) final verification testing. Share on Facebook Share on Twitter Share on Goolge Plus Share on LinkedIn. The constituent elements of the blade are so devised as to require no weight corrections, a feature which makes for good blade balancing and interchangeability. Consecutive steps in manufacturing the blade comprise covering the above mentioned members with an envelope or covering made of a fabric of fibres pre-impregnated with a polymerizable synthetic resin, then possibly adding a leading-edge cap or the like made of metal or of a resilient substance, such as polyurethane, and a trailing-edge member, and finally assembling all these members by sticking and hot polymerisation. Unidirectional fiberglass and other reinforced plastic have significant advantages over metals for blade construction. Whole forms a `` torque-tube '' to the blade for design variables is chosen the! 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