Helicopter assemblies, helicopter KSS

Helicopter units. Each unit has its own functional purpose.

Frame helicopter aggregates (fuselage tail, wing) are structures that receive loads from aerodynamic forces and forces coming from the units installed therein and systems arising at different flight modes.

Ball screw (HB) is a kinematic device that provides creation of the aerodynamic forces and moments for the motion, balancing and control helicopter.

Mechanical control is designed to transmit a pilot effort to change the aerodynamic load on the executive administration (the blade screws, stabilizer console).

Transmission (drives) distributes the engine power consumers - HB, the tail rotor (PB), energy systems (hydraulic, electrical, heat transfer systems, etc.), transforming it in accordance with the needs of the torques.

The chassis receives load during landing and maneuvering on the runway.

Thus, the basic units of the helicopter as a distinguished based on their functions, and the conditions of their work. Therefore, the formation of the KCC and KKC has its own specific features in the design methodology.

Engines, hydraulic aggregates, oil system, the electrical system in the practice of helicopter design bureau are finished products generated at the specialized enterprises.
The general criterion for assessing the appropriateness of the KCC and KKC is full compliance with the functional purpose and meeting the selected criteria optimization (minimum mass and cost of ownership, reliability, operational efficiency, etc.).

Consider a few examples of successful solutions of these basic units of the helicopter.

The MD-500 was originally designed as a light military surveillance and communications helicopter. One of the additional tasks was the transfer of four soldiers over short distances.
Particular attention is drawn to the simplicity of construction and low cost of manufacture and operation of the helicopter.

The designers have used very uncluttered power circuit of the fuselage, consisting of two transverse strength of the frames, separating the fuselage into several compartments: a cabin for two crew members, a compartment for the payload (squatting there were placed four soldiers), the fuel cell at the bottom of the fuselage, engine compartment and in the rear compartment of the main rotor gearbox. It is easy to see that all the concentrated forces: the thrust of the main rotor, the load on the chassis Polozkov etc. - Perceived most rational way.

For the Ka-50 helicopter, the power structure of the fuselage is a "trunk" structure formed by four flat surfaces that penetrate the entire length of the fuselage (in the form of a barrel) and dissected by force diaphragms (frames) into a number of functional compartments. The external contours of the fuselage (except for the tail boom) do not carry any loads, except aerodynamic and inertial from their own mass, and can easily be modified. Such a solution allowed to radically simplify the problems of access to assemblies during assembly, repair and maintenance, while ensuring the necessary strength and rigidity of the structure.

Introduction to the Spanish engineer Juan de la Cierva hinges in the rotor hub (rotor) was of fundamental importance. In the history of ideas is a helicopter that decision allowed for real flights to the main rotor at sufficiently low strength characteristics of the then existing materials.

Advances in materials science in recent years has allowed to abandon the rolling bearings, always limiting the longevity of such a loaded and the unit responsible, as is the hub of the rotor. As an example, the design of the hub of the helicopter MD-500 (torsion plate of high-strength steel) (1.1.2), the hub of the helicopter in-105 (1.1.3), the hub of the Mi-28 elastomeric bearings (1.1.4).
 

The firm "Kamov" boosters conventionally generates power control system in the form of one common unit. This solution allows to simplify trassygidro systems and improve their reliability. The most interesting design solution of this module is to block the PC for 60F Ka ~ 32A twin boosters in each control channel (1.1.5).
The proposal of the Russian engineer BJ Zherebtsova make hydraulic rack chassis dampers helicopters also wore two-chamber principle. It was this decision made it into the hands of designers tool to solve the problem of "earthly" resonance (1.1.6).

Assemblies and units of equipment