1 GENERAL DESIGN

GENERAL DESIGN AND LAYOUT

The Ka-50 is a single-seat, two-rotor (coaxial) attack helicopter powered by two turbo shaft engines and supported by tricycle landing gear.

1-1: Ka-50 Drawings

The Ka-50 fuselage is designed as a non-pressurized, semi-monocoque structure that is divided into several sub-compartments - rectangular in midsection. Two joints sub-divide the airframe into front / rear parts and a tail unit. The fuselage is built mostly of aluminum alloys and polymer composite materials (organic plastic, carbon – fiber plastic, and honeycomb filler). The Ka-50 airframe is composed of frames, spars, ribs, heavy-duty and light-load panels, as well as door and hatch reinforcements, beams, and a stress-resistant skin. The airframe uses "hanging" panels to streamline the fuselage. The helicopter's fixed stub-wings provide additional lift and serve as weapon attachment points. Each stub-wing is equipped with two pylons for carrying weapons, fuel tanks, and pods. The tail unit includes a vertical stabilizer, the main horizontal fins, and widely-spaced aerodynamic rudders at the ends of the horizontal fins.

1-2: Helicopter with open access covers and disassembled wing The retractable, wheeled tricycle landing gear consists of a forward strut and two main heavy-duty struts with a 2,600mm track and a 4,911mm base. The front strut tires are pressurized to 8±0.5 kgf/sq.cm, and the main strut tires are pressurized to 6.5±0.5 kgf/sq.cm.. In flight, the struts are retracted rearwards into the fuselage bays, the main struts being covered by shutters.

POWER PLANT AND ROTOR SYSTEM

The Ka-50 power plant incorporates two TV3-117VMA turbo shaft engines, transmission gear boxes, power plant systems, and devices. The engines include a free-running turbine and a pneumatic turbo-drive starting system. The torque from the turbines is transmitted through the intermediate and main reducing gears. Each engine measures 2055x650x728mm and develops 2,200 hp at take off with a fuel consumption of 137 g/(hp • hr).

1-3: The exhaust nozzle of auxiliary power unit (in operation) and screen-type exhaust devices of main engine

The main engine compartments and the Auxiliary Power Unit (APU) housing are separated by fire-proof partitions. Both engines are equipped with centrifugal dust filters and screen-type exhaust devices that mix external air with exhaust gas

to suppress the helicopter‟s emissions in the infrared band. The transmission system includes one main and two intermediate gears that serve to transmit power output from the main engines to the rotors and adjust their rate of rotation. The engines are designed to be started independently by means of a free-wheeling clutch that disengages one or both engines from the main reducing gear and supports helicopter flight with a single running engine or in autorotation descent mode. The main reducing gear is equipped with the front and rear drive boxes that incorporate the helicopter‟s system units and the main rotor braking mechanism. The auxiliary power plant incorporates the AI-9V gas-turbine engine and a pneumatic drive to feed compressed air to the turbo drive and main engines' start-up system.

The Ka-50‟s main rotor system is made up of two triple-blade coaxial rotors and blade control units. The upper rotor (top view) rotates clockwise and the lower rotates counterclockwise. The main rotor heads are unhinged, and the blades are attached to them through the torsion bars installed in self-lubricating bearings. The blade spars are designed as hollow beams of variable section with glass-carbon plastic partitions. The helicopter tail unit is glued to the spar's butt section. Its skin and rib facings are made of organic plastic with a polymer, honeycomb plastic filler. The blades' swept ends are fixed to the spars at an angle of 33°. The helicopter‟s fuel system is comprised of two primary tanks and up to four external fuel tanks. The front tank serves to feed fuel to the port side engine, and the rear tank provides fuel to the starboard engine and to the auxiliary power unit (APU). Both primary tanks are made of kerosene-resistant rubber-fiber material. The tanks' bottoms and two-thirds of their walls are protected by layers of natural rubber. Additionally, the tanks contain polyurethane foam with an elastic, porous filler to prevent a fuel explosion if it is hit by enemy fire.

1-4: Assembly of main rotor

GENERAL PURPOSE EQUIPMENT

The Ka-50‟s hydraulic system drives the hydraulic actuating mechanisms of the helicopter. Mechanisms served by hydraulics power include the control surface drives, the braking mechanisms of the landing gear main struts, the landing gear extension and retraction cylinders, and the cannon control units. The flight control system of the Ka-50 incorporates pitch, roll, and yaw inputs and the general pitch control unit. The flight control hydraulic inputs are then combined in the control drive unit that ensures reliable operation in both the irreversible manual control system mode and the combined control

mode (i.e., the mode combining manual control and auto-piloted flight stabilization). The Electrical Power System uses three-phase 115 V 400 Hz AC power that is supplied by two generators with an output of 80 kW and a 500 W converter. The 27 V DC supply is supplied through rectifiers. On the ground, the helicopter can also be connected to a 115 V 400 Hz external power supply unit. The Ka-50‟s Warning System includes the SAS emergency warning system and the EKRAN built-in warning and control system. A Series 3 Tester U3 flight data recorder serves to record and store helicopter flight parameter data and system performance data from the last three hours of flight in case of emergency. The unit is capable of recording 38 analog and 63 digital signals. Safety of the magnetic tape is ensured by the "black box", which is sealed to be heat and impact-proof.

1-5: EKRAN built-in warning and control system (left) and auxiliary flight indicator (right)

The KKO-VK-LP oxygen supply system feeds oxygen to the pilot when at altitudes up to 6,000 m. The pilot's oxygen supply set consists of an oxygen bottle, an oxygen mask with a hose, and a gas mask. The 2-litre oxygen bottle is capable of supplying the pilot 90 minutes of air.

The deicing system prevents icing of the helicopter's most vital systems, such as the engine air intakes and dust-filtering devices, the main rotor blades, the windshield, the air pressure sensors, the angle of attack and yaw sensors, the clock, and the icing visual indicator. Additionally, the cockpit windshield and the Shkval-V protective glass cover are equipped with defrosting liquid sprinklers and wipers. The helicopter emergency escape system includes the K-37-800 pilot ejection system, the main rotor blade cut-off system, the cockpit escape hatch system, the ejection system attachments, and the control system.

RADIO EQUIPMENT

The Ka-50 radio communications suite includes two R-800L1 and one R-868 VHF transceivers; an automatic data transmission system that updates ground controllers of the helicopter‟s position and performance; the SPU-9 intercom system; the P-503B device that records any signals coming through the pilot's headphones; and the Almaz-UP-48 voice message unit (VMU) system that is capable of providing voice warning reports to the pilot of eleven types of flight emergency situations. The Ka-50 is also equipped with an IFF transponder, the ARK-22 radio compass, and the A-036A radio altimeter.

The PrPNK “Rubikon” (K-041) piloting, navigation, and targeting system combines digital and analog information systems with digital combat-flight information processors. The Rubikon is based on an integrated computer system that includes five sub-units: four BCVM 20-751 computers (combat, navigational, data display, and target designation), one BCVM 80-30201 computer (weapons control systems), and one UVV 20M-800 data input/output device.

1-6: The tail od the Ka-50. The white navigation light is near the top of the image. The sensor of L-140 laser warning system is in the middle of the picture and various IFF antenaes are located to each side and below it.

The I-251V Shkval-V targeting system incorporates TV com-ponents, a laser range finder and target designator, and a laser beam-rider system for the Vikhr ATGM system. The Shkval also provides image stabilization, variable field of views, and an automatic target-tracking system once a target is designated. The electro-optical television sensor has either a wide or narrow field of view, with line-of-sight deflection angles of +35° in azimuth and from +15° to -80° in elevation. The IT-23MV indicator displays a monochrome image produced by the Shkval television system. The RANET indication system displays targeting, piloting, and navigational information on the ILS-31 head-up display (HUD). Its other purpose is to create the shapes and symbols that are displayed on the IT-23MV indicator. RANET provides a 24-degree field-of-view against the backdrop of the ILS-31 screen. Advanced Map Moving System (AMMS):

Flight preparation and planning

Cartographic support for all stages of mission

Processing of information from the linked systems

Output of information to linked systems

Navigation calculations for mission

The AMMS enables:

 Programming, editing and saving of waypoints, runways, radio beacons, target locations and the ability to study terrain along the flight route, etc.

 Ability to alter flight plan during mission

 Real-time determination of helicopter position coordinates by using built in navigational satellite system sensor (NAVSTAR/GLONASS); display of the helicopter position on the electronic moving map display; ability to cycle map scale and check cross-track error, and other necessary navigation information

 Display of aeronautical information and flight plan required for navigation during all stages of a mission

 Reception of information from the autonomous pressure altitude sensors and necessary processing of pressure altitude for the needs of the built-in satellite navigation system sensor

 Reception and processing of information from the other avionics systems such as the “Rubicon” targeting-navigation system and data link equipment.

 Indicating the position of wingmen using data link as well as targeting line of sight vector from the “Shkval” targeting system

 Annotate moving map with text and symbols

1-7: “ABRIS” AMMS system

The Obzor-800 target designation system is mounted on the pilot's helmet and generates control signals for the Shkval-V weapons system. Target designation is accomplished by the pilot turning his or her head within +60° (azimuth) and -20° to +45° (elevation).

The PNK-800 Radian piloting and navigation system functions as a subsystem to the Rubikon system and it affects the automated piloting and navigation systems in

combination with the other system components. The Radian incorporates the C-061K pitch-and-heading data system and the IK-VSP-V1-2 speed-and-altitude data system.

CONTERMEASURES SYSTEMS

The Ka-50 is equipped with the L-140 Otklik laser detection system that is capable of detecting and identifying laser guidance systems and range finders. The UV-26 system is used to dispense infrared flare decoys and dipole reflectors are carried in two 26mm cartridge pods that are fixed to the wing tips. Each pod contains 64 cartridges.

1-8: UV-26 falres dispenser, port side (red) navigation light and the singal flares dispenser.

PERFORMANCE CHERACTERISTIICS

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