摘要:
Flow separation behind the notch region (21) of a swept tip (12) of a helicopter rotor blade (11) is reduced by features of the geometry and aerodynamic characteristics of the notch region itself. In particular it has been found beneficial for a forwardly swept leading edge portion (16) to extend at an angle between 30 degrees and 55 degrees from a reference line parallel to a blade pitch change axis (31) and the leading edge of the aerofoil in the notch region incorporates blade droop (30).
摘要:
Flow separation behind the notch region (21) of a swept tip (12) of a helicopter rotor blade (11) is reduced by a plurality of boundary layer control vanes (22) located adjacent a forwardly swept leading edge portion (16) forming the notch region (21).
摘要:
A backshell for connecting screened multi-core cables includes a tubular body portion which in a preferred embodiment includes a plurality of circumferentially arranged holes one of which, in use, receives the free end of an electrically conductive ribbon wound round the wires of the cable and in contact with their individual screens. Rotation of the body portion winds the ribbon around the periphery of the cable until the space is filled, the ribbon being wound externally round the tubular body portion and secured with termination means whereby the individual screens are connected electrically to the backshell. Attachment means facilitate attachment of the backshell either to a cylindrical connector body or to a hollow box member for connection in turn to a rectangular connector body.
摘要:
A method for producing a component having a wedge-shaped cross section from fibre reinforced plastic material comprises laying a plurality of sheets of such material in a stack with adjacent sheets staggered in a widthwise direction, cutting the stack longitudinally to form two part stacks, joining the part stacks so that the cut edges form a common edge of the joined part stacks and consolidating and curing the assembly to form the component.
摘要:
The swept extreme tip edge (35) of a helicopter rotor blade (11) incorporates blade droop to reduce aerodynamic pitching moments caused by spanwise flow encountered in the fore and aft sectors of a rotor rotational disc during forward flight of a helicopter on which the blade is fitted.
摘要:
A single stage method for forming and joining pre-consolidated sheets (15, 16, 19) of fibre-reinforced thermoplastics material each having an adherent polymer layer (23, 24) in those areas that are to be joined comprises locating one of the sheets (15, 16) in a female mould tool cavity (18) which is heated to the fusion bonding temperature of the adherent layers (23, 24). A second sheet (19), located in register with the cavity is heated to its melt temperature and formed to shape by a male mould tool part (20) while simultaneously applying pressure to the areas of the sheets to be joined together to form the component.
摘要:
A helicopter control system comprises a flight control computer (22), an engine control computer (34) and an integrated flight and engine control computer (45), the latter generating output signals operative both in a flight control system and an engine control system to eliminate or reduce transient variations in the speed of rotation of a main sustaining rotor (13). The invention can be used with full or limited authority flight control systems.
摘要:
The swept extreme tip edge (35) of a helicopter rotor blade (11) incorporates blade droop to reduce aerodynamic pitching moments caused by spanwise flow encountered in the fore and aft sectors of a rotor rotational disc during forward flight of a helicopter on which the blade is fitted.
摘要:
A helicopter control system comprises a flight control computer (22), an engine control computer (34) and an integrated flight and engine control computer (45), the latter generating output signals operative both in a flight control system and an engine control system to eliminate or reduce transient variations in the speed of rotation of a main sustaining rotor (13). The invention can be used with full or limited authority flight control systems.