Business, Industry

Mi-2 (helicopter): specifications and photos

The design of the Mi-2 helicopter is a Mi-1 turbine development, in which the whole cabin area has been freed for payload by installing two small gas turbine engines over the fuselage. The creation of a new aircraft became known in the autumn of 1961, and the first Mi-2 appeared two years later with two gas turbine "Izotov GTE-350" with a capacity of 400 liters. from. Each installed side by side over the cabin.

Main goals

The aircraft was designed to perform the same tasks for the transport of lightweight goods, which Mi-1 was engaged in. The passenger variant could transport 7 people and a pilot. In the role of a rescue aircraft, the Mi-2 helicopter accommodates four stretchers and a paramedic. The vessel is capable of carrying loads of up to 700 kg. As a flying crane or for performing rescue operations, an aircraft can be equipped with a ventral hook for a suspended load of up to 800 kg or a winch over the door of the cabin capable of lifting up to 150 kg. The fourth main application, which distinguishes the Mi-2 helicopter, is operation in agriculture, for which it can be equipped with tanks placed on both sides of the cabin, capable of accommodating 450 kg of dry chemicals or 500 liters of liquid. For other tasks, the cargo tanks can be replaced by additional fuel tanks.

History of creation

The helicopter Mi-2 (see photo in the review) was produced at the WSK plant in Mielec, Poland. After negotiations, begun in January 1964, WSK received exclusive rights to manufacture the aircraft and its engines. It was supposed that he would replace Mi-1 in military aviation and would be especially valuable for Aeroflot as an ambulance and an air taxi. Some Mi-2 are believed to have been delivered to the UAR, from where they probably landed in Israel.

In the mid-fifties, the Mile Bureau decided to improve the performance of the Mi-1 by developing its turbine version. For this purpose, two new gas turbine engines with a free turbine "Izotov GTD-350" were selected. At a weight of half the mass of the previous reciprocating internal combustion engines, two GTE-350s were 40% more powerful. They are mounted side by side over the fuselage, which significantly increases the available space of the cabin and improves the characteristics of the Mi-2 helicopter. Such a power plant allowed to change the speed of rotation of the screw, maintaining constant engine speed.

The prototype of the aircraft was called B-2, and then it was renamed into Mi-2. The helicopter took off for the first time in September 1961. It had the same rotor, transmission and tail fins as the Mi-1. After preliminary tests, a metal steering screw was adopted (it was wooden in Mi-1), and then, from 1965, a new rotor bearing bushing, borrowed from the Mi-6, appeared.

Since the Soviet plants were fully engaged in the production of the Mi-8 and other heavy Mi-series helicopters, an agreement was reached with WSK-Swidnik on the production and further development of the Mi-2 in Poland, which began in 1964. The first Polish Mi-2 before that He flew in November 1963, and after the completion of the tests in 1965, his large-scale production began. The first production helicopter Mi-2 was equipped with 400-liter engines. With., But since 1974 this parameter has been increased to 450 liters. from. The use of fiberglass in the main rotor, tail rotor and stabilizer simplified production and increased productivity.

For military and civilian purposes, various versions of the Mi-2 were built. The helicopter, which was in service with the Polish Air Force, was equipped with rocket launchers and air-to-ground missiles that were fired from the rails on the sides of the fuselage.

Modifications

Mi-2: a standard civilian helicopter, a convertible passenger or cargo transport, a pollinator (called Bazant), a training aerial vehicle for aerial photography and photogrammetry, or a cargo carrier with an external suspension and electric winch.
Mi-2B: basic model with updated navigation aids and electric system without anti-glare rotor blades. The passenger version weight was 2300 kg, and the cargo version - 2293 kg.
Mi-2D Przetacznik: military air command post with radio communication, encryption and telephone equipment.
Mi-2P: standard passenger eight-seat helicopter, convertible in all-cargo with an external suspension and electric winch.
Mi-2P: agricultural version for conventional or ultra-small spraying and spraying. On both sides of the fuselage, tanks with a capacity of 500 liters of liquid or 375 kg of dry chemicals were hung, and a 14-m spray bar with 128 nozzles was attached. Weight without load - 2,372 kg.
Mi-2 Platan: helicopter mining.
Mi-2RL: air ambulance and search and rescue version of Mi-2, equipped with an electric lift.
Mi-2RM Anakonda: version of search and rescue helicopter Mi-2R for naval use with electric winch through port side door, designed for two people and dumped from the air with boats. 9 units were built for Polish naval aviation.
Mi-2Ro: military reconnaissance modification.
Mi-2RS Padalec: helicopter chemical and bacteriological exploration.
Mi-2S: Medevac air ambulance, equipped to carry four stretchers accompanying, and two patients in the sitting position.
Mi-2SZ: training helicopter with double control.
Mi-2T: military transport.
Mi-2URN: the Mi-2US variant of 1973, but with two Mars 2 launchers, each of which holds 16 57-mm unmanaged S-5 missiles for direct air support or armed reconnaissance.
Mi-2URP Salamandra: anti-tank model of Mi-2 helicopter, 1976 version with four AT-3 guided missiles ("Baby" 9M14M) on pylons and four more in cargo hold; Later models were equipped with four missiles "Arrow 2".
Mi-2URGG Gniewosz: similar to the Mi-2URP, but with four anti-aircraft missiles SA-7 (9M32 "Strela").
Mi-2US: combat helicopter equipped with a 23 mm cannon NS-23KM from the port side of the fuselage, two machine guns on the sides and two machine guns of the caliber of 7.62 mm in the rear of the cabin.
Mi-2FM Kajman: version for photogrammetry. 2 units were produced.
Mi-2X Chekla: a helicopter of radiation reconnaissance and a director of smoke screens.
UM-2Ro: training reconnaissance option.

Mi-2MSB

The Ukrainian version of the Mi-2MSB installed engines AI-450M "Motor Sich" with a capacity of 465 liters. from. With 27% less fuel consumption and 25 kg less weight. The helicopter avionics has also been updated. The variant is equipped with pylons with eight 80 mm B8W8MSB rocket launchers and automatic grenade launchers. Due to the fact that the pylons pass through the rear windows without changing the design of the fuselage, machine-guns can be mounted from the outside of the cockpit from outside the helicopter.

Additional 7.62-mm machine guns can be located in the windows of the helicopter. In addition, under the tail beam, along with the system of IR-jamming, there is a device for launching signal rockets. These elements provide partial protection against anti-aircraft missiles with infrared guidance, which pose the greatest threat to military helicopters.

Technical description of Mi-2 helicopter

The carrier system is a three-bladed screw with hydraulic vibration dampers. The blade profile is NACA 230-12M. Blades do not stack. The rotor brake is installed. The main shaft of the screw is driven by a reducer of each engine. The transmission includes a three-stage main reduction gear, intermediate and tail gear.

The coefficient of reduction of the turbine rotation for the main rotor is 1: 24.6, for the steering screw - 1: 4,16. The main reducer provides a drive for auxiliary systems and a power take-off for the rotor brake. The freewheel clutch disconnects the rotor from the failed engine, allowing its self-rotation.

Initially, each blade had a typical design of all Mil helicopters, consisting of 20 connected sections attached to an alloy alloy spar with a trailing edge made from honeycomb aluminum and coated with a light alloy sheet. Later, WSK-PZL-Swidnik developed more advanced rotor blades based on an extruded duralumin spar with plastic sections and coating.

The system of strengthening the control lever of the cyclic and collective pitch is hydraulic; The adjustable mounting angle controlled by the common pitch lever has a horizontal stabilizer.

The fuselage of sheet duralumin is connected by spot welding or rivets. It consists of three main nodes - the bow, central and tail beam; Elements bearing load, reinforced with alloy steel.

Chassis

Mi-2 is a helicopter with a non-slip three-wheeled chassis with a tail support. In the front there is a double wheel and one wheel is mounted in the main part. Oil-air shock absorbers are installed on all supports, including the tail. The main shock absorbers are able to cope with both normal workloads and with possible ground resonance. The main tires measure 600x180 mm at a pressure of 4.41 bar. Nasal - in the size 400х125 mm, pressure 3,45 bar. The main wheels are equipped with pneumatic brakes. Metal aerial skis are optional.

Power point

The Mi-2 helicopter engine is a 313-kW turbogenerator "Izotov GTD-350" built in Poland. Two such gas turbine units are mounted side by side over the cabin of the aircraft. The only fuel tank of rubber with a capacity of 600 liters is located under the floor of the cabin. On both sides of the helicopter it is possible to mount additional external tanks with a volume of 238 liters. The filling station is located on the right side of the housing. The volume of oil is 25 liters.

Accommodation

Usually one pilot is in the cockpit on the left side. The air-conditioned salon provides seats for 8 passengers - oriented back-to-back benches for 3 people each with two additional side seats on the starboard side rear, one after the other. All passenger seats can be dismantled to carry up to 700 kg of cargo. Access to the salon is provided through doors on hinges on each side in the front of the cab and the stern on the left. Sliding window of the pilot in emergencies is squeezed out. In the rescue modification, there is a place for 4 stretchers and a medical attendant, or 2 stretchers and 2 sitting patients. In the training version, the seats are located side by side and there is a double control. Mi-2 helicopter with standard heating, ventilation and air conditioning systems.

Systems

The salon is heated by air heated by the engine. For ventilation in cold weather, the temperature of the atmospheric air rises in the heat exchangers.

The hydraulic system has a pressure of 65 bar and is designed to strengthen the lever of the cyclic and common pitch. The flow rate of the hydraulic fluid is 7.5 l / min. The tank is ventilated. The pneumatic system has a pressure of 49 bar and is designed to operate the brake.

The power supply is provided by starter generators driven by two STG-3 3kW engines, as well as by a 3-phase alternator with a power of 16 kVA and 208V voltage. 24V DC power supply is provided by two 28Ah lead-acid batteries. The main and steering screws, the windshield are equipped with an electric anti-icing system. The air intake is heated by air drawn from the engine.

Avionics

Standard elements include two MF / HF transceivers, a gyrocompass, a radio compass, a radio altimeter, an intercom system and a blind flight panel. Some military modifications are equipped with a nose and tail warning radar.

Equipment

The agricultural version of the helicopter on each side of the fuselage is equipped with a tank with a total capacity of 1000 liters of fluid or 750 kg of dry chemical and either a nozzle rack in the rear of the cabin on both sides or a spray of dry chemicals on each tank. The width of the spray grip is 40-45 m.

In the rescue version, an electric winch with a carrying capacity of 120 kg is installed. Cargo ventral hook can be mounted for lifting suspended goods up to 800 kg by weight.

At the director of the smoke screen, long additional pipes are attached to the exhaust pipes, into which fuel is supplied. The windscreen of the pilot is equipped with an electric windshield wiper. In addition, in the engine compartments and compartment of the main reducer, a freon fire extinguishing system is installed, which is activated automatically or manually.