Unified management of collective pitch of the main rotor, and engines
Unified management of collective pitch of the main rotor, and engines

Joint control of the common pitch of the main rotor and engines


Management NV and common step motors helicopter collective pitch lever carried 1, which is cinematically connected to the slide by a lever AP 10 and 8 levers at the same time the fuel assembly located on the engines.

Collective pitch lever with locking system in any position to the left of the pilot seat. For fixing lever are friction device with manual or hydraulic control.

A change in the overall step is associated with controlling the power of the helicopter engines either by mechanical kinematic coupling, or automatically via a speed regulator. In both cases, it is ensured that the specified speed of the HB is maintained when the total pitch changes, because Simultaneously, the engine power is changed accordingly. In the case of mechanical connection of the step to the gas, the step handle has a special rotary compensation handle connected to the throttle (fuel feed lever) of the engine. With the help of this handle, the pilot can correct the rotation speed of the HB within the permissible limits regardless of his pitch.

Automatic speed control when changing its HB collective pitch angle of attack and airspeed of the helicopter is usually carried out by changing the fuel supply to the engine. Autonomous control system of the power plant can be located directly inside the engine. It provides a change in its capacity as a hand in a range from idle

before take-off mode, and automatic maintenance of the set speed constant NV. This engine control system can work without manual operation "step-gas", ie collective pitch lever can only change the value of the step without moving the lever of the fuel supply, which should be transferred to the "automatic". Rebuilding speed controller, it is possible to change the range limit, it is necessary to obtain optimal operating conditions of the power plant as a function of altitude and airspeed.

collective control

There's also another system of automatic speed control NV, in which the stabilizer is used - an automatic fuel control is included in the board manual "step-gas" through the sliding rod. The pilot may at any time intervene in the management. The stabilizer may be turned off in the event of any malfunction. Sliding Rod working on stabilizing the speed is automatically set as the neutral position, the capacity for normal manual control.

The speed range of the speed regulator via the pull rod can be up to 40-50% of the full stroke of the fuel feed lever on the engines. The inclusion of a speed regulator in the incomplete control range increases safety when it fails. At the same time, the presence of manual control enables the pilot to intervene in control during sudden changes in the flight regime and to increase the range necessary for the stabilizer. In case of failure of one of the engines, the machine outputs the working engine to increased power up to takeoff and above - depending on the flight mode. In the presence of a speed stabilizer, the pilot does not use the correction handle, but it is advisable to save it for operation in the event of an automation failure.

On helicopters with two or more engines, other than of a "step-gas", establishes a system of separate power control engines. The reduction of engine power is achieved by moving the lever down (away from you), an increase - moving the lever up (to itself). These levers are substantially on the ground in the separate engine testing and in emergency cases in flight, if necessary restarting of a failed engine.

To separate off the engines in the cockpit has control handle stop valves, located in a convenient place to manage.

For emergency engine shutdown (in case of fire) the pilot can further cut off fuel to the engine by means of fire hydrants.

To improve the characteristics of balancing single-rotor helicopter collective control NV, usually associated with the stabilizer 4. Especially important this relationship is to go to the modes of motor planning and autorotation. The control unit is connected to the slider stabilizer AP.

The dependence of changes in the angle of installation of the stabilizer of the total step HB.

In order to minimize the deviation of the AP ring to the minimum, the thrust 3 going to the rockers of longitudinal or lateral control should be sufficiently long and positioned as perpendicular to the direction of displacement of the slider. The significance of this undesirable relationship is small. On light helicopters special kinematics can be applied, completely eliminating the relationship between longitudinal and transverse control from the common step. However, the use of such a scheme on heavy helicopters leads to a significant increase in the mass of the elements of the mechanical control wiring.

Kinematic HB control circuit may be configured so that the three channels operate simultaneously three MG. Such kinematic scheme of the State Control HB ensures the independence of control channels NV, to create an optimal KSS AP and reduce the need to strengthen security on stocks GIs.


I will not go into the details of the assembly, but the above options work only considered the ideal in other cases it situatsii.tak emergency such as the angle of attack depends on HB gidracha. so for example during acceleration and angle of rise-takeoff will be dramatically different. that is, a start on my part is necessary because when overclocking HB angle must change towards umenscheniya degrees step. I want to give a special dimension to the critical angle of attack of the propeller.