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In forward flight, a helicopter's flight controls behave more like those in a fixed-wing aircraft. Moving the cyclic forward makes the nose pitch down, thus losing altitude and increasing airspeed. Moving the cyclic back makes the nose pitch up, slowing the helicopter and making it climb.
Cyclic/collective pitch mixing (CCPM) is a control concept employed in collective pitch radio-controlled helicopters. [1] CCPM reduces mechanical complexity and increases precision of control of the helicopter rotor's swashplate. Unlike conventional systems in which a single actuator is responsible for a single axis, CCPM mechanisms allow ...
To control the collective pitch of the main rotor blades, the entire swashplate must be moved up or down along its axis without changing the orientation of the cyclic controls. Conventionally, each control mechanism, (roll, pitch, and collective) had an individual actuator responsible for the movement.
In 1943, primary investor G & J Weir Ltd. revived the moribund Cierva Autogiro Company to develop an experimental helicopter to Air Ministry Specification E.16/43. The W.9 was to investigate James G. Weir's contention that a powered tilting hub-controlled rotor with automatic collective pitch control, and torque reaction control using jet efflux, was both safer and more efficient than the ...
This type of differential pitch control, known as cyclic pitch, allows the helicopter rotor to provide selective lift in any direction. The swashplate can also transfer a combined static pitch increase to all rotor blades, which is known as collective pitch.
Coaxial rotors solve the problem of main rotor torque by turning each set of rotors in opposite directions. The opposite torques from the rotors cancel each other out. Rotational maneuvering, yaw control, is accomplished by increasing the collective pitch of one rotor and decreasing the collective pitch on the other. This causes a controlled ...
Original helicopter "classes" were based on the engine size. For example, a helicopter with a 0.30 cu in (4.9 cm 3) engine was a 30 class and a helicopter with a 0.90 cu in (14.7 cm 3) engine was referred to as a 90 class helicopter. The bigger and more powerful the engine, the larger the main rotor blade that it can turn and hence the bigger ...
The signs of VRS are a vibration in the main rotor system [8] followed by an increasing sink rate and possibly a decrease of cyclic authority. [9]In single rotor helicopters, the vortex ring state is traditionally corrected by slightly lowering the collective to regain cyclic authority and using the cyclic control to apply lateral motion, often pitching the nose down to establish forward flight.