Layout diagram of the Mi 8 helicopter. Russian Aviation
- a medium multi-purpose helicopter that is used for passenger and cargo transportation. It performs a wide range of tasks in any region of the planet.
The development of the V-8 (Mi-8) helicopter began at the Design Bureau named after. M.L. Mil (now JSC Moscow Helicopter Plant named after M.L. Mil, part of the Russian Helicopters holding company) in May 1960 to replace the Mi-4 multi-purpose piston helicopter, which had proven itself in operation. The Mi-8 was created as a deep modernization of the Mi-4 helicopter with a gas turbine engine. The helicopter was developed simultaneously in two versions: the passenger Mi-8P and the transport Mi-8T.
The first prototype of the new helicopter (with one engine and a four-blade rotor) took off in July 1961, the second (with two engines and a five-blade rotor) - in September 1962, the first flight of the prototype helicopter took place in 1962.
Serial production of the Mi-8 began in 1965 at OJSC Kazan Helicopter Plant and OJSC Ulan-Ude Helicopter Plant.
In 1964-1969, seven world records were set on Mi-8 helicopters (mostly by female helicopter pilots).
The Mi-8 exceeds the Mi-4 helicopter in maximum load capacity by 2.5 times and in speed by 1.4 times. The transmission of the Mi-8 helicopter is similar to the Mi-4 helicopter.
The helicopter is made according to a single-rotor design with a tail rotor, two gas turbine engines and a tricycle landing gear.
The main rotor blades are all metal. They consist of a hollow spar pressed from an aluminum alloy. All main rotor blades are equipped with a pneumatic spar damage alarm. The control system uses powerful hydraulic boosters. Mi-8 is equipped with an anti-icing system that operates in both automatic and manual modes. The helicopter's external suspension system allows it to transport cargo weighing up to 3000 kilograms.
If one of the engines fails in flight, the other engine automatically switches to increased power, while horizontal flight is performed without reducing altitude. The Mi-8 is equipped with an autopilot that provides stabilization of roll, pitch and yaw, as well as constant flight altitude. Navigation and flight instruments and radio equipment that the helicopter is equipped with allow it to fly at any time of the day and in difficult weather conditions.
The helicopter is mainly used in transport and passenger versions. In the passenger version, the helicopter (Mi-8P) is equipped to transport 28 passengers. By special order, in Kazan, a version with a luxury cabin can be manufactured, designed for seven passengers. Such orders were carried out for Boris Yeltsin, Nursultan Nazarbayev, Mikhail Gorbachev.
Military option Mi-8T has pylons for hanging weapons (unguided missiles, bombs). The next military modification of the Mi-8TV has reinforced pylons for hanging a large number of weapons, as well as a machine gun mount in the bow of the cabin.
Mi-8MT— modification of the helicopter, which was the logical conclusion of the transition from a transport to a transport-combat helicopter. More modern TVZ-117 MT engines with an additional AI-9V gas turbine unit and a dust protection device at the entrance to the air intakes are installed. To combat surface-to-air missiles, there are systems for dispersing hot engine gases, shooting false thermal targets and generating pulsed IR signals. In 1979-1988, the Mi-8MT helicopter took part in the military conflict in Afghanistan.
The Mi-8 can be used to solve a wide variety of tasks: for fire support, suppression of fire points, delivery of troops, transportation of ammunition, weapons, cargo, food, medicine, evacuation of the wounded and dead.
The helicopter is unpretentious and trouble-free. The Mi-8 abroad, and here too, is called a “workhorse”, a “soldier’s machine”.
Mi-8 helicopters are the most common transport helicopters in the world.
In the history of the world helicopter industry, in terms of the total number of machines produced - over 12 thousand (about 8,000 in Kazan and over 4,000 in Ulan-Ude) - the Mi-8 helicopter has no analogues among devices of its class.
In terms of the number of modifications, the Mi-8 is a world record holder. There are more than a hundred of them. Modifications were created at the Moscow Helicopter Plant named after. M. L. Mil, at the Kazan and Ulan-Ude factories, repair enterprises, directly in military units and Aeroflot detachments, as well as abroad during operation.
GENERAL CHARACTERISTICS OF THE MI-8T HELICOPTER
1. GENERAL INFORMATION ABOUT THE HELICOPTER
The Mi-8 helicopter is designed to transport various cargoes inside the cargo compartment and on an external sling, mail, passengers, as well as for carrying out construction, installation and other work in hard-to-reach areas.
Rice. 1.1. Mi-8 helicopter (general view)
The helicopter (Fig. 1.1) is designed using a single-rotor design with a five-blade main rotor and a three-blade tail rotor. The helicopter is equipped with two TV2-117A turboprop engines with a take-off power of 1,500 hp. each, which ensures high flight safety, since flight is possible even if one of the engines fails.
The helicopter is operated in two main versions: the passenger Mi-8P and the transport Mi-8T. The passenger version of the helicopter is designed for interregional and local transportation of passengers, baggage, mail and small-sized cargo. It is designed to carry 28 passengers. The transport option provides for the transportation of cargo weighing up to 4000 kg or passengers in the amount of 24 people. At the request of the customer, the passenger cabin of the helicopter can be converted into a cabin with increased comfort for 11 passengers.
The passenger and transport versions of the helicopter can be converted into an ambulance version and into a version for operation with an external sling.
The ambulance version of the helicopter allows you to transport 12 bedridden patients and an accompanying medical worker. In the version for working with external sling, large cargo weighing up to 3000 kg is transported outside the fuselage.
For long-range helicopter flights, it is possible to install one or two additional fuel tanks in the cargo compartment.
Existing versions of the helicopter are equipped with an electric winch, which allows, using an onboard boom, to lift (lower) loads weighing up to 150 kg on board the helicopter, and also, if there is a pulley system, to pull wheeled loads weighing up to 3000 kg into the cargo compartment.
The helicopter crew consists of two pilots and a flight mechanic.
When creating the helicopter, special attention was paid to high reliability, efficiency, ease of maintenance and operation.
Safety of flights on the Mi-8 helicopter is ensured by:
The installation of two TV2-117A(AG) engines on the helicopter, the reliability of the operation of these engines and the VR-8A main gearbox;
The ability to fly in the event of failure of one of the engines, as well as switch to autorotation mode (self-rotation of the main rotor) in the event of failure of both engines;
The presence of compartments that isolate the engines and main gearbox using fire barriers;
Installation of a reliable fire protection system that ensures extinguishing a fire in the event of its occurrence, both simultaneously in all compartments and in each compartment separately;
Installation of backup units in the main systems and equipment of the helicopter;
Reliable and effective anti-icing devices for main and tail rotor blades, engine air intakes and cockpit windshields, which allows flight in icing conditions;
Installation of equipment that ensures simple and reliable piloting and landing of a helicopter in various meteorological conditions;
Drive of the main units of the systems from the main gearbox, ensuring the operability of the systems in the event of engine failure:
The ability to quickly leave the helicopter after landing by passengers and crew in emergency situations.
2. BASIC HELICOPTER DATA
Flight data
(transport and passenger options)
Take-off weight (normal), kg.................. 11100
Maximum flight speed (instrument), km/h, 250
Static ceiling, m........................ 700
Instrument cruise speed at altitude
500 m, km/h ……………………………………………220
Economic flight speed (instrument), km/h. 120
fuel 1450 kg, km................................ 365
option with fuel filling 2160 kg, km. . .620
Flight range (at an altitude of 500 m) in ferry
option with fuel filling 2870 kg, km... 850
Flight range (at an altitude of 500 m) with refueling
fuel 2025 kg (outboard tanks of increased
capacity), km................................................... .. 575
Flight range (at an altitude of 500 m) in ferry
version with fuel filling 2735 kg (outboard tanks
increased capacity), km.... 805
Flight range (at an altitude of 500 m) in ferry
version with fuel refueling 3445 kg (outboard tanks
increased capacity), km.... 1035
Note. Flight range is calculated taking into account 30 minutes of fuel remaining after landing
Geometric data
Helicopter length, m:
without main and tail rotors................... 18.3
with rotating main and tail rotors ...25,244
Helicopter height, m:
without tail rotor................................... 4.73
with rotating tail rotor................ 5.654
Distance from the tip of the main rotor blade to
tail boom when parked, m.................. 0.45
Distance from ground to bottom of fuselage
(clearance), m................................................... ...... 0.445
Horizontal tail area, m 2 ..... 2
Helicopter parking angle................. 3°42"
Fuselage
Cargo compartment length, m:
without cargo doors........................ 5.34
with cargo doors at 1 m from the floor 7.82
Cargo compartment width, m:
on the floor................................................ ... 2.06
for heating ducts........................ 2.14
maximum........................................ 2.25
Cargo compartment height, m.................. 1.8
Distance between power floor beams, m ... 1.52
Escape hatch size, m…………………… 0.7 X1
Loading ramp track, m.................. 1.5±0.2
Passenger cabin length, m............ 6.36
Passenger cabin width (floor), m... 2.05
Passenger cabin height, m 1.8
Seat pitch, m................................................... .... 0.74
Passage width between seats, m... 0.3
Wardrobe dimensions (width, height, depth), m 0.9 X1.8 X 0.7
» sliding door (width, height), m. 0.8 X1.4
» opening, along the rear entrance door in the passenger
option (width, height), m.......... 0.8 X1>3
Size of emergency hatches in passenger compartment
option, m........................................ 0, 46 X0.7
Crew cabin size, m................... 2.15 X2.05 X1.7
Adjustment data
Angle of installation of the main rotor blades (according to the rotor pitch indicator):
minimum................................................. 1°
maximum........................................ 14°±30"
Deflection angle of the trimmer plates of the propeller blades -2 ±3°
» installation of tail rotor blades (at r=0.7) *:
minimum (left pedal all the way) ................... 7"30"±30"
maximum (right pedal all the way)………….. +21°±25"
* r- relative radius
Weight and centering data
Take-off weight, kg:
maximum for transport option…….. 11100
» with a load on an external sling …………… 11100
transport option........................... 4000
on external sling......................... 3000
passenger version (person).......... 28
Empty helicopter weight, kg:
passenger version........................... 7370
transport »................................ 6835
Weight of service load, including:
crew weight, kg................................... 270
» oil, kg................................................... ............. 70
weight of products, kg................................................... 10
» fuel, kg................................................... .......... 1450 - 3445
» commercial load, kg........................ 0 - 4000
Empty helicopter alignment, mm:
transport option........................................ +133
passenger » ..................................... +20
Acceptable alignments for a loaded helicopter, mm:
front................................................... ............. +370
rear................................................... .................... -95
3. AERODYNAMIC AND GEOMETRIC CHARACTERISTICS OF THE HELICOPTER
According to the aerodynamic design, the Mi-8 helicopter is a fuselage with a five-bladed main rotor, three-bladed tail rotor and fixed landing gear.
The main rotor blades are rectangular in plan with a chord equal to 0.52 m. The rectangular plan is considered aerodynamically worse than others, but it is easy to manufacture. The presence of trimmer plates on the blades allows you to change their torque characteristics.
The blade profile is the most important geometric characteristic of the rotor. The helicopter has different profiles along the length of the blade, which significantly improves not only the aerodynamic characteristics of the main rotor, but also the flight properties of the helicopter. From the 1st to the 3rd section, the NACA-230-12 profile is used, and from the 4th to the 22nd - the NACA-230-12M profile (modified) *. The NACA-230-12M airfoil has Mkr = 0.72 at an angle of attack of zero lift. As the angle of attack a° increases (Fig. 1.2), Mcr also decreases at the most favorable angle of attack, at which the lift coefficient C y = 0.6, Mcr = 0.64. In this case, the critical speed in the standard atmosphere above sea level will be:
V KP == a Mkr = 341 0.64 = 218 m/s, where a is the speed of sound.
Consequently, at the ends of the blades it is possible to create a speed of less than 218 m/s, at which shock waves and wave resistance will not appear. At the optimal rotor speed of 192 rpm, the peripheral speed of the blade tips will be:
U = wr = 2 prn / 60 = 213.26 m/s, where w is the angular velocity;
r is the radius of the circle described by the tip of the blade.
Rice. 1.2. Change in the lift coefficient C y from the angles of attack a° and the M number of the NACA-230-12M profile
This shows that the peripheral speed is close to the critical speed, but does not exceed it. The helicopter main rotor blades have a negative geometric twist, varying linearly from 5° at the 4th section to 0° at the 22nd section. In the section between the 1st and 4th sections there is no twist and the installation angle of the blade sections in this section is 5°. Twisting the blade by such a large amount significantly improved its aerodynamic properties and the flight characteristics of the helicopter, and therefore the lift force is more evenly distributed along the length of the blade.
* The compartment from the 3rd to the 4th section is transitional. Main rotor blade profile - see fig. 7.5.
The propeller blades have variable both absolute and relative profile thickness. The relative thickness of the profile c is 13% in the butt, in the area from r = 0.23 to 7 = 0.268 - 12%, and in the area from r = 0.305 to the end of the blade - 11.38%. Reducing the thickness of the blade towards its end improves the aerodynamic properties of the propeller as a whole by increasing the critical speed and Mkr of the end parts of the blade. Reducing the thickness of the blade towards the tip leads to a decrease in drag and a decrease in the required torque.
The main rotor of a helicopter has a relatively large fill factor - 0.0777. This coefficient makes it possible to create greater thrust with a moderate propeller diameter and thereby keep the blades in flight at small installation angles, at which the angles of attack are closer to the most advantageous ones in all flight modes. This made it possible to increase the efficiency of the propeller and delay stalling at higher speeds.
Rice. 1.3. Helicopter rotor polarity in hovering mode: 1 - without ground influence; 2 - with the influence of the earth.
The aerodynamic characteristics of a helicopter main rotor are presented in the form of its polar (Fig. 1.3), which shows the dependence of the thrust coefficient Cp and the torque coefficient tcr on the total pitch of the main rotor<р. По поляре видно, что чем больше общий шаг несущего винта, тем больше коэффициент крутящего момента, а следовательно, больше коэффициент тяги. При наличии «воздушной подушки» тяга несущего винта будет больше, чем без нее при том же шаге винта и коэффициенте крутящего момента.
The tail rotor blades are rectangular in plan with the NACA-230M profile and do not have geometric twist. The presence of a combined horizontal joint of the “universal joint” type and a flapping compensator at the tail rotor hub allows for a more even redistribution of the lift force over the surface swept by the propeller in flight.
The helicopter fuselage is aerodynamically asymmetrical. This can be seen from the curves of changes in the coefficients of fuselage lift C 9f and drag coefficient C depending on the angle of attack a f (Fig. 1.4). The lift coefficient of the fuselage is zero at an angle of attack slightly greater than 1, therefore the lift force will be positive at angles of attack greater than G, and negative at angles of attack less than 1. The minimum value of the fuselage drag coefficient C will be at an angle of attack equal to zero. Due to the fact that at angles of attack greater or less than zero the coefficient C f increases, it is advantageous to fly at angles of attack of the fuselage close to zero. For this purpose, a forward tilt angle of 4.5° is provided for the main rotor shaft.
A fuselage without a stabilizer is statically unstable, since an increase in the angle of attack of the fuselage leads to an increase in the coefficient of longitudinal moment, and, consequently, the longitudinal moment acting on pitching up and tending to further increase the angle of attack of the fuselage. The presence of a stabilizer on the tail boom of the fuselage provides longitudinal stability to the latter only at small installation angles from +5 to -5° and in the range of small angles of attack of the fuselage from -15 to + 10°. At large angles of installation of the stabilizer and large angles of attack of the fuselage, which corresponds to flight in autorotation mode, the fuselage is statically unstable. This is explained by the disruption of flow from the stabilizer. Due to the helicopter having good controllability and sufficient control margins in all flight modes, it uses a stabilizer that is not controllable in flight with an installation angle of 6°.
Rice. 1.4. Dependence of the lift coefficient Suf and drag coefficient Схф of the fuselage on the angle of attack a° of the fuselage
In the transverse direction, the fuselage is stable only at large negative angles of attack -20° in the range of gliding angles from -2 to + 6°. This is due to the fact that an increase in the sliding angles leads to an increase in the roll moment coefficient, and consequently, the lateral moment, which tends to further increase the sliding angle.
In terms of direction, the fuselage is unstable at almost all angles of attack at small sliding angles from -10 to +10°; at angles greater than these, the stability characteristics improve. At sliding angles of 10°< b < - 10° фюзеляж нейтрален, а при скольжении больше 20° он приобретает путевую устойчивость.
If we consider the helicopter as a whole, although it has sufficient dynamic stability, it does not cause any great difficulties when piloting even without an autopilot. The Mi-8 helicopter is generally rated with satisfactory stability characteristics, and with the automatic stabilization systems turned on, these characteristics have improved significantly, the helicopter is given dynamic stability in all axes and therefore piloting is significantly easier.
4. HELICOPTER LAYOUT
The Mi-8 helicopter (Fig. 1.5) consists of the following main parts and systems: fuselage, takeoff and landing devices, power plant, transmission, main and tail rotors, helicopter control, hydraulic system, avionics and electronic equipment, cabin heating and ventilation systems , air conditioning systems, air and anti-icing systems, devices for external load suspension, rigging, mooring and household equipment. The helicopter fuselage includes a nose 2 and central 23 parts, a tail 10 and end 12 beams. In the bow, which is the cockpit, there are pilot seats, instrument panels, electric consoles, an AP-34B autopilot, and command control levers. The glazed cockpit provides good visibility; the right 3 and left 24 blisters are equipped with emergency release mechanisms.
In the forward part of the fuselage there are niches for installing containers with batteries, airfield power plug connectors, air pressure receiver tubes, two taxi and landing lights and a hatch with a cover 4 for access to the power plant. The forward part of the fuselage is separated from the central part by connecting frame No. 5N, in the wall of which there is a doorway. A folding flight mechanic's seat is installed in the door opening. At the front, on the wall of frame No. 5N, there are shelves for radio and electrical equipment, at the rear there are containers for two batteries, a box and an electric winch control panel.
In the central part of the fuselage there is a cargo compartment, to enter which there is a sliding door 22 on the left, equipped with an emergency release mechanism. A side boom is attached to the outside of the upper front corner of the sliding door opening. In the cargo compartment, folding seats are installed along the right and left sides. On the floor of the cargo compartment there are mooring units and an electric winch. The engines, fan, main gearbox with swashplate and main rotor, hydraulic panel and consumable fuel tank are located above the cargo compartment.
Shock absorbers and struts of the main 6, 20 and front landing gear, outboard fuel tanks 7, 21 are attached to the fuselage components from the outside. A kerosene heater is located in front of the right outboard fuel tank.
The cargo compartment ends in a rear compartment with cargo doors. In the upper part of the rear compartment there is a radio compartment in which panels for radio and electrical equipment are installed. There is a hatch to enter the radio compartment and tail boom from the cargo compartment. Cargo doors cover the opening in the cargo compartment, intended for rolling in and out of wheeled vehicles, loading and unloading large cargo.
In the passenger version, 28 passenger seats are attached to special profiles located along the floor of the central part of the fuselage. On the starboard side in the rear of the cabin there is a wardrobe. The right side panel has six rectangular windows, the left - five. The rear side windows are built into the emergency hatch covers. The cargo doors in the passenger version are shortened, the luggage compartment is located on the inside of the left door, and the boxes for containers with batteries are located in the right door. There is an opening in the cargo doors for the rear entrance door, consisting of a door and a ladder.
Rice. 1.5 Layout diagram of the helicopter.
1-front chassis leg; 2-nose fuselage; 3, 24-sliding blisters; 4-engine exit hatch cover; 5, 21 main landing gear legs; 6-hood heater KO-50; 7, 12-outboard fuel tanks; 8-hoods; 9-gear frame; 10-central part of the fuselage; 11-hatch cover in the right cargo door; 12, 19-load doors; 13-tail boom; 14-stabilizer; 15-end beam; 16-fairing; 17-tail support; 18 ladders; 20-sash flap; 23-sliding door; 25-emergency hatch-window.
The tail boom is attached to the central part of the fuselage, to the nodes of which the tail support and the uncontrolled stabilizer are attached. The tail shaft of the transmission runs inside the tail boom in its upper part. An end beam is attached to the tail boom, inside of which an intermediate gearbox is installed and the end part of the transmission tail shaft passes through. A tail gearbox is attached to the end beam on top, on the shaft of which a tail rotor is mounted.
The helicopter has a non-retractable tricycle landing gear. Each landing gear is equipped with liquid-gas shock absorbers. The wheels of the front strut are self-orienting, the wheels of the main struts are equipped with shoe brakes, for the control of which the helicopter is equipped with an air system.
The power plant includes two TV2-117A engines and systems that ensure their operation.
To transmit power from the engines to the main and tail rotors, as well as to drive a number of units, a transmission is used, consisting of main, intermediate and tail gearboxes, a tail shaft, a fan drive shaft and a main rotor brake. Each engine and main gearbox has its own autonomous oil system, made according to a direct single-circuit closed circuit with forced oil circulation. To cool the engine oil coolers and main gearbox, starter generators, alternators, air compressor and hydraulic pumps, the helicopter is equipped with a cooling system consisting of a high-pressure fan and air ducts.
The engines, main gearbox, fan and panel with hydraulic units are covered by the hood. When the hood covers are open, free access to the units of the power plant, transmission and hydraulic system is provided, while the open hood covers of the engines and main gearbox are working platforms for performing maintenance of helicopter systems.
The helicopter is equipped with means of passive and active fire protection. Longitudinal and transverse fire partitions divide the engine compartment into three compartments: the left engine, the right engine, and the main gearbox. The active fire protection system supplies extinguishing agent from four cylinders to the burning compartment.
The main rotor of a helicopter consists of a hub and five blades. The bushing has horizontal, vertical and axial hinges and is equipped with hydraulic dampers and centrifugal blade overhang limiters. The all-metal construction blades have a visual spar damage alarm system and an electrothermal anti-icing device.
The tail rotor is a pusher, pitch variable in flight. It consists of a cardan-type hub and three all-metal blades equipped with an electrothermal anti-icing device.
The helicopter's dual control consists of longitudinal-transverse control, directional control, combined "Pitch-throttle" control and main rotor brake control. In addition, there is separate control of engine power and engine shutdown. Changing the overall pitch of the main rotor and longitudinal-transverse control of the helicopter are carried out using a swashplate.
To ensure control of the helicopter, the system of longitudinal, transverse, directional control and collective pitch control includes irreversible hydraulic boosters, for powering which the helicopter has a main and backup hydraulic systems.
The four-channel AP-34B autopilot installed on the Mi-8 helicopter ensures stabilization of the helicopter in flight in roll, heading, pitch and altitude.
To maintain normal temperature conditions and clean air in the cabins, the helicopter is equipped with a heating and ventilation system that supplies heated or cold air to the crew and passenger cabins. When operating a helicopter in areas with a hot climate, instead of a kerosene heater, two onboard freon air conditioners can be installed.
The helicopter's anti-icing system protects the main and tail rotor blades, the two front windows of the cockpit and the engine air intakes from icing.
The anti-icing device for the propeller blades and cockpit windows is electrothermal, and the engine air intakes are air-thermal.
The aviation and radio-electronic equipment installed on the helicopter ensures flights day and night in simple and difficult weather conditions.
At the end of the 1950s, work began abroad and here on the creation of second-generation helicopters with turboshaft engines, and in May 1960. at the Moscow Helicopter Plant the development of a new multi-purpose helicopter began to replace the multi-purpose helicopters that have proven themselves in operation Mi-4 . The first experimental helicopter AT 8 , with one gas turbine engine AI-24V designs by S.P. Izotov and a four-blade main rotor from a helicopter Mi-4 , designed to carry 25 passengers, made its first flight in June 1961, and on July 9 it was first demonstrated at an air festival at the Tushino airfield in Moscow; several helicopters were built.
The main attention was paid to the development of a twin-engine helicopter with a new five-bladed main rotor, developed on the basis of modified all-metal helicopter blades Mi-4 , and a new rigid tail rotor. Second experimental helicopter AT 8, with two gas turbine engines TB2-117 power by 1267kW, made its first flight on September 17, 1962, successfully passed flight tests and since 1965. began mass production at the helicopter plant in Kazan under the designation Mi-8. A number of original technical solutions were used in the design of the helicopter: large-sized duralumin stampings and glue-welded joints, a new external suspension system, an automatic engine control system that ensures their synchronization and maintaining the rotor speed within specified limits. Compared to a helicopter Mi-4 the new helicopter had higher flight characteristics and twice the payload capacity. By helicopter Mi-8 in 1964-1969 7 international records were set, most of which were women's, set by pilots L.G. Isaeva, N.A. Kolets and T.V. Russiyan, and unsurpassed to this day.
Helicopters Mi-8 are the most common transport helicopters in the world, second only to light multi-purpose and transport Bell UH-1 "Iroquois" And "Huey" . In total, more than 8,000 helicopters were produced Mi-8 at the Kazan Helicopter Plant and the Aviation Plant in Ulan-Ude, of which more than 2,000 were exported to more than 40 countries, where half of them are still in operation.
Helicopters Mi-8 were produced in more than 30 different civil and military modifications, among which the main ones:
- Mi-8P- passenger helicopter with gas turbine engine TV2-117A power by 1267kW, with a cabin for 28 passengers and square windows;
- Mi-VPS "Salon"- a passenger helicopter with a high-comfort cabin for 11 passengers with an eight-seat common seat on the right side and two seats and a rotating seat on the left side, improved interior trim and a ventilation system and a toilet; also produced in versions with a cabin for 9 and 7 passengers;
- Mi-8T- transport helicopter with gas turbine engine TV3-117MT power by 1454 kW, for transportation of goods weighing 4000kg in the cabin, or 3000kg on an external sling, or 24 passengers on the side seats, or 12 patients on stretchers with accompanying persons; It is distinguished by small round cabin windows and equipment; in military versions it is equipped with pylons with holders for weapons.
- Mi-8TG- modification of the Mi-8T helicopter with gas turbine engine TV2-117TG power by 1103kW, developed in 1987, the world's first helicopter that uses liquefied petroleum gas along with aviation fuel;
- Mi-8TV- a landing transport helicopter for the armed forces with reinforced truss pylons with four holders for blocks of 32 NAR caliber 57mm or other weapons and a mobile installation with a machine gun caliber 12.7mm in the bow, it is possible to install triple holders for weapons from six blocks of 32 NAR, and on guide rails up to six ATGMs AT-2 with semi-automatic control; also produced in an export version with six ATGMs AT-3 with manual control. More than 250 helicopters Mi-8TB And M.T. were converted into Mi-17 .
- Mi-8MT- modernized airborne transport helicopter with gas turbine engine TV3-117MT power by 1454kW, with dust protection devices, auxiliary power unit AI-9V and a tail rotor mounted on the left to increase efficiency; the helicopter is a transitional model to an improved helicopter Mi-17 ; was produced in variants Mi-8AM And MI-8MTV with various equipment and weapons and in the variant Mi-8MTB-1A for civil use;
- Mi-8PP- active jamming helicopter with a container and cross-shaped dipole antennas on the sides of the fuselage; A number of modifications were also built for electronic warfare, relaying, etc.
- Mi-9- a helicopter to provide communication with additional antennas on the tail boom;
- Mi-18 - military transport helicopter, helicopter modification Mi-8T with a cabin length increased by 1 m, which made it possible to accommodate more than 38 soldiers or cargo weighing 5-6.5t, and on the external sling - loads weighing 5t. In 1980 two helicopters Mi-8MT have been modernized to Mi-18 with an enlarged cabin, new fiberglass blades and a retractable tricycle landing gear, and in 1982. passed flight tests that confirmed an increase in payload capacity with an increase in speed and flight range by 10-15%;
- Mi-8MTV-2 And 3 - the latest military transport modifications, intended for use in airborne transport, ambulance, rescue and combat versions, with weapons from four blocks B8V20-A 20 NAR each S-8, the firing of which is controlled by the PUS-36-71 sight; it is possible to mount aerial bombs with caliber 50-500kg on beam holders BDZ-57KRVM; in the bow there can be placed a mobile installation with a machine gun caliber 12.7mm, in the sliding door openings there are up to 8 pivot installations with machine guns of caliber 7.62mm, and on the holders - 4 gun containers UPK-23-250 with guns GSh-23L caliber 23mm what does a helicopter do Mi-8MTV-2 the most heavily armed in the world. To dissipate the heat flow of the gas turbine engine, screen-exhaust devices are installed, and to protect against guidance missiles with an IR system, the helicopter is equipped with a passive jamming system consisting of 4 ACO-2B cassettes on the tail boom and 6 cassettes on the fuselage; Each cassette contains 32 PPI-26-1 IR decoys and pulsed IR signal generators. The helicopter is equipped with armor plates covering the floor, front and rear parts of the cockpit and hydraulic panel. The helicopter can be equipped with radar and long-range navigation radio equipment;
- Mi-8AMTSH- combat helicopter variant Mi-8AMT, with a complex of supersonic ATGMs "Storm"; demonstrated at the Farnborough Aerospace Exhibition in September 1996.
DESIGN. The helicopter is made according to a single-rotor design with a tail rotor, two gas turbine engines and a tricycle landing gear.
The helicopter fuselage has a frame structure and consists of the nose and central parts, tail and end beams. In the bow there is a three-seat crew cabin, consisting of two pilots and a flight mechanic. The cabin glazing provides good visibility; the right and left sliding blisters are equipped with emergency release mechanisms. In the central part there is a cabin with dimensions of 5.34 x 2.25 x 1.8 m in the transport version with a cargo hatch with doors that increase the length of the cabin to 7.82 m, and a central sliding door with dimensions of 0.62 x 1.4 m with an emergency release mechanism; mooring units and an electric winch are located on the floor of the cargo compartment, and an electric winch boom is installed above the door. The cargo compartment is designed to transport cargo weighing up to 4 tons and is equipped with folding seats for 24 passengers, as well as attachment points for 12 stretchers. In the passenger version, the cabin has dimensions of 6.36 x 2.05 x 1.7 m and 28 seats, two installed on each side with a pitch of 0.74 m and a passage of 0.3 m; in the rear of the cabin there is a wardrobe on the right, and in the rear of the doors there is an opening for the rear entrance door, consisting of doors and a ladder.
The tail boom is a riveted beam-stringer type structure with working skin, equipped with units for attaching a controlled stabilizer and a tail support.
Stabilizer with a size of 2.7 m and an area of 2 m 2 with a NACA 0012 profile of a single-spar design, with a set of ribs and duralumin and fabric covering.
The chassis is tricycle, non-retractable, the front support is self-orienting, with two wheels measuring 535 x 185 mm, the main supports are of a shaped type with liquid-gas double-chamber shock absorbers and wheels measuring 865 x 280 mm. The tail support consists of two struts, a shock absorber and a support heel; chassis track 4.5m, chassis base 4.26m.
Main rotor with hinged blades, hydraulic dampers and pendulum vibration dampers, installed with a forward inclination of 4° 30". All-metal blades consist of a pressed spar made of AVT-1 aluminum alloy, hardened by work hardening with steel hinges on a vibration stand, a tail section, a steel tip and tip The blades have a rectangular shape in plan with a chord of 0.52 m and NACA 230 profiles with a relative thickness of 12% to 11.38% and a geometric twist of 5%, the peripheral speed of the blade tips is 217 m/s, the blades are equipped with a visual alarm system for spar damage and an electrothermal anti-icing device. .
The tail rotor with a diameter of 3.9 m is three-blade, pushing, with a cardan-type hub and all-metal blades of rectangular shape in plan, with a chord of 0.26 m and a NACA 230M profile.
The power plant consists of two turboshaft gas turbine engines with a free turbine TV2-117AT of the St. Petersburg NPO named after. V.Ya.Klimov with a take-off power of 1250 kW per Mi-8T or TVZ-117MT - 1435 kW per Mi-8MT, AMT And MTB, installed on top of the fuselage and closed by a common hood with opening flaps. The engine has a nine-stage axial compressor, an annular combustion chamber and a two-stage turbine. Engine length 2.835m, width 0.547m, height 0.745m, weight 330kg. The engines are equipped with dust protection devices.
The fuel system consists of a consumable fuel tank with a capacity of 445 l, a left outboard tank of 745 or 1140 l, a right outboard tank of 680 or 1030 l, an additional tank of 915 l in the cargo compartment.
The transmission consists of main, intermediate and tail gearboxes, brake shafts, and a main rotor. The VR-8A three-stage main gearbox provides power transmission from engines with an output shaft rotation speed of 12,000 rpm to the main rotor with a rotation speed of 192 rpm, the tail rotor - 1,124 rpm and the fan - 6,021 rpm for cooling , engine oil coolers and main gearbox; The total capacity of the oil system is 60 kg.
The control is duplicated, with rigid and cable wiring and hydraulic boosters driven from the main and backup hydraulic systems. The AP-34B four-channel autopilot ensures stabilization of the helicopter in flight in roll, heading, pitch and altitude. The main hydraulic system with a working pressure of 4.5 MPa provides power to all hydraulic units, and the backup one, with a pressure of 6.5 MPa, provides power only to the hydraulic boosters.
Equipment. The heating and ventilation system supplies heated or cold air to the crew and passenger cabins; the anti-icing system protects the main and tail rotor blades, the front windows of the cockpit and engine air intakes from icing.
Equipment for instrument flights in difficult meteorological conditions day and night includes two ARB-ZK attitude indicators, two NV rotation speed indicators, a GMK-1A combined heading system, an ARK-9 or ARK-U2 automatic radio compass, and an RV-3 radio altimeter.
Communication equipment includes VHF command radios R-860 and R-828, HF radios R-842 and Karat, and an aircraft intercom SPU-7. On Mi-8T There is RI-65 voice communication equipment to notify the crew about in-flight emergencies. On military variants Mi-8MT an IR jamming station "Linden", a screen-exhaust device for suppressing IR radiation from engines, containers with LC, and an armored cockpit were installed.
At the request of the customer, an external load suspension system is installed: cable for 3000 kg and articulated-pendulum for 2500 kg and a winch with a lifting capacity of 150 kg.
Armament. Military versions use a machine gun with a caliber of 12.7 or 7.62 mm in the nose mobile installation, built-in holders on shaped pylons on the sides of the fuselage for installing up to six NAR units with up to six ATGMs placed on top on guide rails. Containers with machine guns or cannons can also be suspended on pylons, and machine guns and grenade launchers can be mounted on pins in the blisters and side openings of the cargo compartment.
E.I.Ruzhitsky "Helicopters", 1997
Technical data Mi-8T
Power point: 2 x GTD TV2-117A power by 1250kW, main rotor diameter: 21.29m, fuselage length: 18.17m, height: 4.38m, fuselage width: 2.5m, take-off weight: 12000kg, empty weight: 6625kg, maximum speed: 250km/h, cruising speed: 225km/h, dynamic ceiling: 4500m, range of flight:
If you are looking for a car suitable for the role of a “collective image” of a helicopter of the USSR (and Russia), then, without a doubt, it will be the Mi-8. It has been in production since the 1960s - for more than fifty years. During this time, it became one of the most common helicopters in history and in the world, and among twin-engine machines, the G8 is the most popular.
And as of 2015, the Mi-8 is generally the third most common among aircraft in general. But what’s even more remarkable is that it is still being produced and is not going to give up its positions. Of course, many of the G8’s peers are still in service, but in terms of versatility and relevance it still has no equal.
History of the Mi-8
The date of birth of the Mi-8 is February 20, 1958. On this day, the Council of Ministers adopted a resolution on the experimental construction of a medium helicopter, then called “B-8”. The head of the design bureau, Mikhail Mil, planned to use the experience gained during the creation by creating a replacement for the medium Mi-4.
Replacing the piston engine with two turbines promised not only to improve performance, but also to rationalize the layout of the helicopter.
In those years, American companies also abandoned piston engines, replacing them with gas turbines. The power plant of many piston helicopters (including the Mi-4) was usually bulky star-shaped engines that occupied the entire forward part of the fuselage. This placement forced the pilot's cabin to be moved upstairs, and the space of the cargo compartment to be occupied by drive shafts.
The B-8 was initially designed as a multi-purpose aircraft - both the Air Force and Aeroflot were customers.
Passenger, military transport and armed versions were considered.
The first B-8, which took off in the summer of 1961, was a passenger plane, with a comfortable cabin for 18 people. True, the prototype was single-engine. Development of the twin-engine B-8A started later and it flew only in 1962.
The next experimental vehicles were a military transport for 20 paratroopers, equipped with a heavy machine gun mount, and a helicopter for government transport. The fifth prototype became the reference model, and serial production of the Mi-8 began in 1965.
Design and device
The Mi-8 helicopter is built according to the classic single-rotor design. The helicopter's fuselage is all-metal, its skin is smooth and functional. In the forward part of the fuselage there is a control cabin with seats for pilots and flight technicians. In the central part there is a cargo compartment (or a passenger cabin, depending on the version). The third part of the fuselage consists of the tail and end booms.
The first Mi-8s were equipped with TV2-117 gas turbine engines with a rated power of 1000 hp. every.
In 1967, development of completely new engines, TV3-117, began on the amphibious version of the Mi-14.
The Mi-8MT helicopter with new engines went into production in 1977. It also featured an auxiliary power unit - a small gas turbine designed to spin the rotors of the main power unit during startup. Previous models were started either from batteries or from an external starter. If one of the engines fails, the second one automatically switches to high power mode, allowing you to complete the flight.
The Mi-8 turbines rotate the propellers through a transmission of three gearboxes - main, intermediate and tail. The main rotor was initially similar to the Mi-4 propeller - all-metal, with four blades. During the tests it was replaced, the number of blades was increased to five. The chassis is wheeled, non-retractable. The nose wheel is self-orienting. The prototype helicopters had wheel fairings, but they were abandoned on production vehicles.
The fuel tanks are external, suspended on the sides. The capacity of the left tank is 1154 liters, the right one, despite the outwardly longer fairing, is 1044 liters. This is explained by the fact that a kerosene cabin heater is located under the fairing of the right tank. Up to two additional tanks with a capacity of 915 liters each can be installed in the cargo compartment. Starting from the Mi-8 MTV model, fuel tanks are protected.
The helicopters were equipped with an AP-34B autopilot. stabilizing the vehicle in roll and pitch (if necessary, both in direction and height). There is a fire-fighting system that allows you to extinguish fire both in the engines and APU, and in the kerosene heater. The hydraulic system is redundant and powers the control system amplifiers.
Helicopter modifications
The number of modifications of the Mi-8 is huge. These include not only passenger and combat vehicles, but also special ones - from fire-fighting versions to marine amphibians. Let's name the main varieties. The main variants of the first series of helicopters with TV2-117 engines were the passenger Mi-8P, transport Mi-8T and combat Mi-8TV. The helicopter for special transportation, with a “superior comfort” cabin, had the index Mi-8PS.
The Mi-14 amphibian was a highly modified Mi-8 with TV3-117 engines. It became a “bridge” to the next generation of Eights, which were exported under the general name Mi-17. In the USSR they were called Mi-8MT. In the 1980s, a new basic model with an increased altitude was launched into production - the Mi-8 MTV. Its improved version was called Mi-8MTV-1, and the universal air assault helicopter received the designation Mi-8 MTV-2.
For export, the new helicopters were sold as the Mi-171, and the modified model for the domestic market became known as the Mi-8 AMT.
In the mid-90s, Russia developed a G8 with improved aerodynamics - the Mi-8MTV-5. The radar installed in the nose of the helicopter required replacing part of the cockpit glazing with an opaque fairing.
Each generation of Mi-8 also included medical modifications, from the Mi-8MB to the Mi-171VA. A number of options were designed for delivery to a specific customer. The Mi-8VSM, an anti-personnel mine layer, also deserves mention. And under the name Mi-9 hides a flying command post for division commanders.
Armament
Initially, only a transport helicopter was developed for the troops, but already in 1968, the military was presented with an armed version of it. And armed very powerfully. Up to six blocks of 57mm unguided rockets, or up to 1500 kg of bombs, were suspended on external consoles. Four Phalanx guided missiles made it possible to fight tanks, and the arsenal was complemented by the installation of a 12.7mm machine gun in the pilot’s cockpit.
In terms of firepower, the Mi-8TV was hardly inferior to the specialized attack aircraft Mi-24, but in terms of security it could not compare with it.
Although the cockpit was additionally protected by armor up to 8 mm thick. A clear disadvantage of the helicopter was its increased weight. Fully loaded with weapons and paratroopers, the vehicle had difficulty taking off, and its flight range decreased.
During the war in Afghanistan, 57mm caliber missiles were replaced with more powerful S-8 80mm caliber analogues. The arsenal was replenished with hanging containers with automatic grenade launchers of 30mm caliber or 23mm cannons.
Flight performance
Let's look at the basic flight performance data of the modern Mi-8 AMT modification and compare it with its competitors. An example will be one of the later modifications of the French Puma - AS.532 and the Sikorsky S-92 helicopter.
| Mi-8 AMT | S-92 | AS.532 | |
|---|---|---|---|
| Length, m | 25,3 | 20,8 | 19,5 |
| Take-off weight, t | 11,1 | 12 | 9,3 |
| Maximum speed, km/h | 250 | 283 | 278 |
| Cruising speed, km/h | 230 | 257 | 257 |
| Ceiling, m | 6300 | 4575 | 4100 |
| Flight range (practical), km | 570 | 999 | 618 |
So, the Mi-8 is larger in size, has a larger ceiling (and a later modification in 2013 rose to a maximum altitude of 9 km), but has a shorter flight range. However, additional tanks can be installed on it.
It is worth noting that the S-92 is a purely civilian vehicle, although it was developed on the basis of the multi-purpose S-70. It may seem strange that the table does not include the obvious rival of the Mi-8 - the Iroquois, or more precisely, the helicopters of the Bell 212/412 family. The fact is that, despite their prevalence, these are cars of a lighter class, with obviously smaller dimensions and carrying capacity.
When the “eights” began to replace the Mi-4, it became clear that their predecessors were inferior to them in everything. The Mi-8 was superior to the “four” in speed, capacity, and ease of maintenance. For example, gas turbine engines freed mechanics from constantly struggling with lubricant leaks. But in one thing the old helicopter could not be surpassed for a long time - it was higher altitude. Therefore, until the appearance of the Mi-8MT modification, piston Mi-4s continued to operate in the mountains.
Although the passenger version of the Mi-8 was among those “developed from the start,” few such vehicles were produced during Soviet times.
But in the 21st century, foreign and Russian orders for passenger helicopters greatly helped the factories.
Quite often, “versatility” is understood as the ability of a machine to do everything, but poorly. The range of tasks that the Mi-8 helicopter solved, and successfully, casts doubt on the fairness of this approach. During his half-century career, he transported cargo and passengers, served in the air forces of African countries and in the Russian Ministry of Emergency Situations.
The Eight operated as an air hospital and a flying crane. Mines were laid and trawled from its side. The helicopter served as an attack aircraft and reconnaissance aircraft. Of course, one could write off its prevalence as an inevitable result of the USSR’s sphere of influence, but the Mi-8 was officially exported to Western countries back in Soviet times. And the demand for it did not stop with the collapse of the Soviet Union. All that remains is to recognize the G8 as a real masterpiece of helicopter engineering.
Video
50 years ago, on August 2, 1962, the first prototype of the Mi-8 multi-purpose helicopter took off for the first time. Mi-8 (NATO classification Hip)- Soviet and Russian multi-purpose helicopter, created by the M.L. Mil Design Bureau in the early 60s of the last century. Currently is the most popular twin-engine helicopter in the world, and is also one of the most popular helicopters in the history of aviation. Widely used to solve a large number of civil and military problems.
The helicopter has been in service with the Soviet Air Force since 1967 and has proven to be such a successful type of equipment that purchases of it for the Russian Air Force continue to this day. Wherein The Mi-8 helicopter is operated in more than 50 countries around the world, including countries such as China, India and Iran.
Over its half-century history of serial production and design work to improve this helicopter, Soviet and Russian designers have created about 130 different modifications, and more than 13,000 machines of this type have been produced. Today these are Mi-8MTV-1, MTV-2, MTV-5, Mi-8AMTSh, Mi-171, Mi-172 helicopters.
In 2012, the Mi-8 is not just a hero of the day - it is a first-class multifunctional helicopter, which today is one of the most successful products of the domestic helicopter industry. Even after 50 years, the car is in demand all over the world and is even purchased by NATO member states. From 2006 to 2008, 26 Mi-171Sh military transport helicopters were delivered to the Czech Republic and Croatia.
Today, the Mi-8/17 production plants of Ulan-Ude Aviation Plant OJSC and Kazan Helicopter Plant OJSC, which are part of the Russian Helicopters holding company, are operating stably and are loaded with orders for the production of these helicopters for 2 years in advance. At the same time, work on modernizing this machine continues continuously.
OJSC Moscow Helicopter Plant named after. M.L. Milya is currently assembling the first prototype of the modernized version of the Mi-171A2 helicopter, and the technical appearance of this helicopter has also been determined. The helicopter was created on the basis of the Mi-171 helicopter and should become a worthy development option for the entire family of Mi-8 helicopters.
It is planned that these helicopters will receive new avionics, and composite materials will be used in the design of the machine, which will make the helicopter significantly lighter. In addition, all the main units and systems of the vehicle were modernized, and its flight and technical characteristics were improved. Total modernization includes about 80 innovations. At the same time, the helicopter crew will be reduced to 2 people, which will significantly affect its economic efficiency.
Over the course of their history, helicopters of the Mi-8 family have taken part in a large number of local conflicts, they have saved thousands of human lives, withstood severe Siberian frosts, catastrophic heat and sudden temperature changes, desert dust and tropical downpours. Mi-8s flew at extremely low altitudes and high in the mountains, were based outside the airfield network and landed in hard-to-reach places with minimal maintenance, each time proving their high reliability and efficiency.
The multi-purpose Mi-8 helicopter, created back in the middle of the last century, is still one of the most popular in its class and will be in demand on the Russian and global aviation markets for many years to come. Over the many years of production, the Mi-8 became the basis for many unique developments, for example, the “amphibious helicopter” Mi-14.
The design of the Mi-8 helicopter
The Mi-8 helicopter is made according to a single-rotor design with a tail rotor, a tricycle landing gear and two gas turbine engines. The fuselage of the vehicle has a frame structure and consists of nose, central, tail and end beams. In the bow of the helicopter there is a crew cabin for three people: two pilots and a flight mechanic. The cockpit glazing provides the helicopter crew with good visibility; the right and left blisters are sliding and equipped with emergency release mechanisms.
In the central part of the fuselage there was a cabin measuring 5.34 x 2.25 x 1.8 meters. In the transport version, it had a cargo hatch with doors, which increased its length to 7.82 m and a central sliding door measuring 0.62 by 1.4 meters, which had an emergency release mechanism. There was an electric winch and mooring units on the floor of the cargo compartment, and an electric winch boom was installed above the door itself.
The helicopter's cargo cabin was designed to transport cargo weighing up to 4 tons and was equipped with folding seats that could accommodate 24 passengers, and there were also attachment points for 12 stretchers. At the customer's request, the helicopter can be equipped with an external cargo suspension system: a hinged-pendulum system for 2500 kg and a cable system for 3000 kg, as well as a winch with a lifting capacity of 150 kg.
In the passenger version of the helicopter, the cabin had dimensions of 6.36 x 2.05 x 1.7 meters and was equipped with 28 seats, which were placed in 2 rows on each side with a pitch of 0.74 m and a passage of 0.3 m. In the rear of the cabin on the right side there was a wardrobe, and in the back of the doors there was an opening for the rear entrance door, which consisted of a ladder and doors.
The tail boom of the helicopter had a riveted beam-stringer type structure and was equipped with a working skin. It was equipped with units for attaching the tail support and the controlled stabilizer. The helicopter was equipped with a stabilizer measuring 2.7 m and an area of 2 m 2 with a NACA 0012 profile; its design was single-spar.
The helicopter's landing gear was tricycle and non-retractable. The front landing gear was self-orienting and consisted of 2 wheels measuring 535 x 185 mm. The main supports of the shaped helicopter were equipped with liquid-gas double-chamber shock absorbers and wheels measuring 865 x 280 mm. The helicopter also had a tail support, which served to prevent the tail rotor from touching the ground. The support consisted of a shock absorber, 2 struts and a support heel. The chassis track was 4.5 meters, the chassis base was 4.26 meters.
The helicopter's power plant included two turboshaft gas turbine engines with a free TV2-117AT turbine produced by the St. Petersburg NPO named after. V.Ya.Klimova. On Mi-8T helicopters its power was 1250 kW, on Mi-8MT, AMT and MTB a TVZ-117MT turbine with a power of 1435 kW was installed. Gas turbine engines were mounted on top of the fuselage and covered by a common hood with opening flaps. The helicopter engines were equipped with dust protection devices and their weight was 330 kg.
Fuel system included a consumable fuel tank with a capacity of 445 liters, a right outboard tank with a capacity of 680 or 1030 liters, a left outboard tank with a capacity of 745 or 1140 liters, and an additional tank in the cargo compartment with a capacity of 915 liters.
The helicopter transmission consisted of 3 gearboxes: main, intermediate and tail, main rotor and brake shafts. The main gearbox of the helicopter provides power transmission from the engines, which have an output shaft speed of 12,000 rpm, to the main rotor with a speed of 192 rpm, as well as the tail rotor with a speed of 1,124 rpm and the fan - 6,021 rpm /min, which serves to cool the main gearbox and engine oil coolers. The total mass of the helicopter oil system is 60 kg.
The helicopter control was duplicated, with cable and rigid wiring, as well as hydraulic boosters, which were driven from the backup and main hydraulic systems. The existing four-channel autopilot AP-34B provided the helicopter with stabilization in flight in terms of heading, roll, altitude and pitch. The main hydraulic system of the helicopter ensured the operation of all hydraulic units, the pressure in the system was 4.5 MPa, the backup system provided only the operation of the hydraulic boosters, the pressure in it was 6.5 MPa.
The Mi-8 helicopter was equipped with a ventilation and heating system, which provided the supply of cold and heated air to the cabins of passengers and crew. The helicopter also had an anti-icing system that protected the steering and main rotor blades, as well as the engine air intakes and the front windows of the cockpit from icing.
Equipment for instrument flights in adverse weather conditions, as well as at night, included an attitude indicator, a combined heading system, a radio altimeter, an automatic radio compass and 2 rotor speed indicators.
Mi-8AMTSH
Currently, the Russian Armed Forces continue to purchase Mi-8 helicopters. As part of the state defense order, Mi-8AMTSh vehicles should be delivered to the troops by 2020. Mi-8AMTSh is an attack military transport helicopter(export designation Mi-171Sh).
The helicopter is designed to combat armored ground, surface, mobile and stationary small targets, to destroy enemy personnel, transport troops, cargo, the wounded, as well as perform search and rescue operations. The helicopter was developed at the Ulan-Ude Aviation Plant in close cooperation with OJSC Moscow Helicopter Plant named after. M.L. Mile."
To solve combat missions, the helicopter can be equipped with a system of missile and small arms and cannon weapons, as well as a set of means of protection against destruction, sanitary and airborne transport equipment, as well as instrumentation and radio-electronic equipment, which allows the helicopter to fly at any time of the day, including and in difficult weather conditions.
At the same time, converting the Mi-8AMTSh helicopter from a combat version to a medical or airborne transport version does not require much time and can be carried out directly during preparation for a flight to perform the corresponding mission.
To increase the combat survivability of the vehicle, this helicopter is equipped with:
— automatic reflector reset ASO-2V;
— ECU screen-exhaust devices;
— a set of removable armor plates that cover the crew;
— protected outboard fuel tanks;
— fuel tanks with polyurethane foam filler.
The crew of the vehicle includes:
– commander – left pilot, is engaged in piloting a helicopter, aims and uses unguided weapons, and performs the “launch” mode when launching guided missiles;
- second pilot, is engaged in piloting a helicopter to assist the crew commander; performs the functions of an operator of the Shturm-V complex when searching for targets, launching and targeting guided missiles, and also performs the duties of a navigator;
– flight mechanic, in addition to performing its regular functions, also performs the functions of a gunner for the stern and bow machine gun installations.
The main distinctive feature of the Mi-8AMTSh helicopters was the inclusion of modern Shturm-V ATGMs and Igla-V air-to-air missiles in their armament. The Sturm complex of high-precision guided missiles makes it possible to quite effectively hit armored vehicles, including those equipped with dynamic protection, low-speed air targets, manpower and fortified enemy positions.
In terms of the range of possible weapons, the MI-8AMTSh comes very close to, while having greater variability in use.
