Ka-25. A photo. History. Characteristics.


Ka-25, which is the codification of NATO called "hormone" - anti-Soviet helicopter ship accommodation.

This is the first in the history of Soviet helicopter anti-submarine helicopter and the first combat helicopter unit. In the beginning it was supposed to be designed exclusively for military use (land impact Mi-24 appeared later in the year 1969).

Is designed in Ka-25 OKB. Kamov, Chief designer was the founder Nikolai Kamov bureau. Production started in the vehicle 1965 year adopted Ka-25 1971 was put in


Later on its base it was released a number of modifications for various applications.

Ka-25 was organized at the aircraft factory number 99, where from at 1965 1973 460 year released copies 18 modifications.

Design Ka-25

Ka-25 is a helicopter with coaxial rotor placement. Two engines are a part of the power plant. The vertical tail of the helicopter is well developed.

The fuselage of this model is made of a duralumin alloy of thickness 0,8 mm. Conditionally it can be divided into two functional parts. In the front part there is a longitudinal power pack, which consists of four power beams and two spars. 18 frames (X of them - power) belong to the transverse power set. The tail beam is composed of eight frames and two spars. On the frames 18 stringers are attached. Sheathing of the tail beam is 3 mm. The windows of the cabin are made of plexiglas (thickness - 3 mm) and equipped with windshield wipers. The helicopter also has an anti-icing system, the principle of which is the use of alcohol-containing solutions on the surface, which can be covered with ice.


The structure of the power plant Ka-25 includes two gas turbine engine GTD-3F producing total power 900 hp, which was done on Omsk Engine Design Bureau. Later it turned out that the power of these engines is not enough to perform some missions. Since 1972 years, the helicopter began to equip engines GTD-3m (1000 hp). Positioning data engines with oil and hydraulic systems, gear, other elements of the power plant at the top of the fuselage area in a rented nacelle.

The equipment fuel system Ka-25 8 refers soft fuel tanks, which are located at the bottom of the fuselage, under the floor of the cab; fuel pumps for various purposes. To add fuel to the tank 200 l to increase the range of flight is possible due to two removable additional tanks, which are mounted on both sides of the fuselage. Modification Ka-25TS has an increased fuel capacity due to the smaller size of the bomb bay. The tanks ASW Ka-modification 25PL placed 1105 kg of kerosene, and Ka-25TS - 1705 kg.

Transmission four-stage planetary gear is represented PB -3F located with motors in the gondola top of the fuselage. Purpose gear is the selection of the power turbine shaft and in addition to the sum.


Carrying system Ka-25 - the two three-blade propeller, each of which has a diameter blades 15,74 m coaxial placement of screws: upper screw rotates clockwise, and the bottom - against.. the blade length - 7,085 m chord -. 0,37 m Each blade consists of a hollow duralumin spar, at the trailing edge of which is attached the profile of 19 tail sections. The front edge of the blade glued rubber.

The structure of the equipment of the bearing system includes the components of the anti-icing complex, which signals the pneumatic installation, which works in the event of cracks in the blade elements, balancing and anti-crumbler loads. Contour lights are at the ends of the blades of the upper screw. Adjustment of the angle of inclination of the blades is carried out due to the lower and upper slots. Save space in the hangars and on the deck of the ship by combining the blades at an angle of 22 ° in a horizontal position manually or by applying the electric blade folding system.

Countering icing of blades is carried out by the anti-icing system. Air intakes blown engines warm air.


In the modification of the Ka-25TS deviation in the plane of rotation of the rudders, control location rotor blades and landing gear hydraulic system responds. Its membership consists of two independent systems: the basic APC 10B and emergency TSA 10-In. They are mounted in a single unit that combines all the installations and units into one.

helicopter chassis is not removed during the flight (except for Ka-25TS). Swiveling front wheels, the main support end brake wheels. Track front and rear wheels is 3,5 1,41 m and m respectively. The base chassis is 3,02 m width and wheel diameter -. X 60 18 cm x 40 15 cm, respectively.

The main terms of reference during the development of the Ka-25 was the implementation of the landing on the deck of the ship at the time of the side and keeled kachek 10 and 3 ° ° and the wind speed 18 m / s.

To ensure a safe landing in such conditions, it was necessary to smash the main landing gear to the side and move back in order to eliminate the possibility of overturning the helicopter's tail.

During the movement of swinging can occur at the site of the marine vessel. For its leveling the helicopter is made fixing the basic pillars to the fuselage by moving farms. This creates a mobility of the chassis in the horizontal direction.


The vertical oscillation during landing on the ship's platform that can reach 2 m / s, are extinguished by the main spring strut supports. They are a series connection of two dampers: low and high pressure. The vibrations that arise from hitting the deck, takes on the high-pressure shock absorber. The second is responsible for the absorption of class "ground resonance" landing and take-off fluctuations.

A multi-section ballonet, mounted in the chassis, helps to safely land on the water, which is filled with compressed air from the cylinders in six seconds. The peculiarity of this filling is that the air that passes through the ejectors sucks in the outboard air. The proportion of outboard air in ballonets is 60%. The operation of the system is not automated and depends on the engine speed. But, despite this, its weight is 260 kg, which significantly increases the aerodynamic drag. Due to the large weight and poor efficiency during the hard landing, it was decided to dismantle it from the construction in 70-ies.


The structure of the electrical part of the generator of alternating current GHS-40U (40 kW), which generates a current voltage 208 B. Emergency envisages involvement of the converter PT1000TSS (1000 W) with voltage output 36 V. This device operates at a clock frequency 400 Hz. Constant current power supply comes from a pair of starter-generators STG-M 6, 28,5 outputs a voltage V and a pair of batteries 15-EDN-45A.

Ka-25 characteristics:

Modification   Ka-25
Diameter of the main rotor, m   15.74
Length m   9.75
Height, m   5.37
Weight, kg empty   4765
Weight, kg normal takeoff   7200
Weight, kg maximum takeoff   7500
engine's type   2 GTE Mars GTD-3F (GTD-3BM)
power, kWt   2 x 671 (738)
Maximum speed km / h   220
Cruising speed, km / h   195
Practical range, km   650
Range, km   400
Practical ceiling, m   4000
Static ceiling, m   600
Crew   2 pilot + operator 2-3
Payload:   up to 12 passengers or 1300 kg of cargo
Armament:   Combat load - 2000 kg in the weapons compartment as much as possible, normally - 650 kg.
 Typical load - 2 anti-submarine torpedoes and / or depth charges



Ka-25. A photo. History. Characteristics.

Ka-25 photo frontKa-25 photo side in flightKa-25 in flight

Ka-25 over the seaKa-25 before plantingKa-25 helicopter scheme

Ka-25 after takeoffKa-25 photo frontKa-25 layout

Ka-25 runwayKa-25 fliesKa-25 cockpit



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