Ka-25 Anti Submarine Helicopter Technical Specifications
- Crew – 2 people + 1 anti-submarine weapons operator
- Engine – 2 x GTD-3F
- Power – 900 hp
- Main rotor diameter-15.74 m
- Empty helicopter weight-4765 kg
- Maximum take-off weight-7500 kg
- Full load weight-1300 kg
- Number of passengers-up to 12 people
- Maximum speed at altitude/near the ground-220 / 195 km / h
- Practical ceiling-4000 m
- Maximum range-450 km
- Combat load-1100 kg (in the armament compartment), including 2 anti-submarine torpedoes AT-1/AT-1M and / or depth charges-4 x PLB-250-120 or 8 x PLB-50-64 / PLAB-MK / OMAB-25-12D / OMAB-25-8N.
- The Ka-25 is the first Soviet anti-submarine helicopter, as well as the first domestic combat helicopter originally designed for combat use.
Ka-25 Anti Submarine Helicopter Details
To solve the tasks set in the late 1950s for the Soviet Navy to gain superiority at sea, fundamentally new helicopter carrier ships were needed to combat enemy missile submarines and surface ships. As a result, there was a need to create a new generation ship helicopter capable of solving the tasks of anti-submarine defense, reconnaissance and target designation, minesweeping, rescue and other operations. Already in 1956, the designers of OKB-2 NI. Kamov began research in the field of creating a ship-based helicopter that could also be used as an anti-submarine one. In 1958, the Air Force, together with the Navy, developed tactical and technical requirements for such a helicopter, which received the designation “product “D”. It was assumed that it would be small in size, to be placed one at a time in the hangars of small anti-submarine ships or to be based in groups in the hangars of large aircraft carriers; to have folding rotor blades; have the ability to take off and land from small platforms on the deck while the ship is moving, when pitching with a deck tilt of up to 10° and up to 3° trim, and also perform a flight in hover mode for more than 1 hour at a distance of 50 km from the home ship. At the same time, the maximum speed was supposed to be 220 km / h, and the flight range was 450 km. Taking into account the experience gained by OKB-2 Kamov in this area, the Ministry of Defense of the USSR instructed him in February 1958 to develop and build a new anti-submarine helicopter equipped with the necessary flight navigation and search and sighting avionics, as well as means of destroying submarines. To develop the engine and gearbox for this helicopter, a special design bureau was organized in Omsk under the leadership of V. A. Glushenkov. At the same time, an AT-1 aircraft torpedo was being developed for the new helicopter. Specialists of TsAGI, CIAM and other organizations were involved in the work.
For the first time, the Kamov OKB-2 had to not only build and test a new helicopter, but also ensure its compatibility with the carrier ship being created at the same time. The helicopter carrier ship, in turn, was supposed to have a runway and parking lots, a command and control center for flight control. In its inter-deck and bilge volumes, it was planned to create hangars for helicopters, compartments for maintenance equipment and fuel and lubricants. In order for the helicopter carrier ship to become a truly effective combat system, the helicopter had to accommodate a modern and multifunctional complex, which had no analogues at that time. Only with its help was it possible to reliably search for submarines, detect surface ships at great distances and transmit their coordinates to your ship and coastal bases – when piloting a helicopter day and night in simple and difficult weather conditions over an undirected water surface. It was assumed that such a complex would ensure the effective use of weapons to destroy enemy nuclear submarines. The project of the ship’s helicopter “D” (K-20) for arming Navy ships of various classes was ready in 1960. The twin-screw coaxial scheme provided this helicopter with small dimensions combined with high maneuverability, especially necessary for ship-based operations. The K-20 helicopter was the first among N. I. Kamov’s machines to use turboshaft engines to rotate the rotors. However, taking into account the fact that the dimensions and weight of the equipment installed on the helicopter turned out to be very large, it was decided to divide the functions and develop two versions of this helicopter at once with a maximum take-off weight of 7000 kg.
The first option is the DB anti-submarine helicopter, a submarine hunter equipped with magnetometric equipment, a sonar station, dropable buoys, a torpedo and other means of destruction. The second option is a DC helicopter, scout, target designator and repeater. In this case, the optimal solution of the combat task was achieved due to a certain combination in the grouping of both types of helicopters.
The first test flight of the new Kamov helicopter was carried out on May 21, 1961, and on July 9 the DB helicopter was first shown to the public at the aviation parade in Tushino. Kamov helicopters have passed a large amount of various tests at sea bases and warships of the fleet. In 1965, serial production of Kamov helicopters under the designation “Ka-25” was launched at plant No. 99 in Ulan-Ude.
On December 2, 1971, the Ka-25 anti-submarine helicopter was officially adopted by the Navy aviation in the basic Ka-25PL anti-submarine version (designed to search for and destroy enemy nuclear submarines with onboard detection and destruction tools at a distance of about 200 km from the home ship), as well as in the Ka-25C target designation helicopter version (to adjust the over-the-horizon targeting of long-range ship missiles). Structurally, both versions of the helicopter were as unified as possible, their difference was only in the special onboard equipment and its placement in the fuselage. In addition, Kamov helicopters in the search and rescue version of the Ka-25PS performed search and rescue tasks for crews in distress at sea, as well as for transporting bulky cargo on an external suspension.
The Ka-25 helicopter was built according to a coaxial scheme. The power plant of the first Ka-25 was equipped with two Glushenkov GTD-3F turboshaft engines with a capacity of 900 hp each and a four-stage RV – 3F planetary gearbox located in a common nacelle in the upper part of the fuselage (since 1974, replaced by more advanced ones-GTD-3BM and RV-3M). For the first time in the domestic helicopter industry, the power plant received an automatic system that maintains the constant speed of the propellers, and an indicator of engine modes. The main propellers are three-bladed, opposite rotation, and the carrier system was distinguished by the presence of de-icing equipment and an electro-hydraulic system for folding the blades over the tail boom when stored on ships. The fuselage is all-metal beam-stringer type. The rear part of the fuselage was a short tail boom, ending in a three-keel tailplane. The two outer keels served as rudders. In the forward part of the fuselage there was a two-seat crew cabin, and the pilot and navigator were located next to each other. The navigator on a movable chair could move to the special equipment compartment and perform the functions of an operator of anti-submarine equipment. The main cabin could also accommodate 12 passengers on folding seats. The chassis is four-legged and non-retractable.
For emergency landing on water, inflatable ballonets were installed on the landing gear racks (dismantled in the mid-1970s). Weapons, including anti-submarine torpedoes and depth charges, were placed in the bomb bay between the landing gear struts. Several search and strike complexes of equipment and weapons were created for the Ka-25 helicopter. So, the Ka-25PL helicopter was equipped with the Baikal search and sighting system, which included: the Initiative-2K radar (the search locator of which was located in the nose fairing); lowered hydroacoustic station VGS-2 “Oka” (located in the rear lower part of the fuselage); hydroacoustic system “Baku” with the SPARU-55 “Pamir” receiving device and 36 dropped hydroacoustic buoys of the type RGB-N “Iva” and RGB-NM “Chinara” (later replaced by buoys of the type RGB-NM1 “Zheton”), which picked up the noise of the submarine’s propellers; radio reception system RPM-S with radar sensors.buoys of the “Float-1A” type; sighting and computing device PVU-V-1 “Jasmine”. Instead of the VGS-2 sonar system, a lowered magnetometer APM-60 “Orsha” (later APM-73) could be installed, fixing the submarine’s hull at depth. The Ka-25PL helicopter’s armament totaled up to 1,100 kg and consisted of 2 AT-1 torpedoes (AT-1M, later T-67) and / or 4 to 8 PLAB-250-120, PLAB-50-64 and PLAB-MK deep-water anti-submarine bombs capable of hitting a submarine at a depth of up to 300 m. In addition, day and night reference-marker bombs OMAB-25-12D and OMAB-25-8N could be suspended from external holders.
In the 1980s, the Ka-25PLS armament was reinforced with KAB-250PL guided bombs and APR-2 rocket-torpedoes. The Ka-25TS variant was distinguished by the presence in the nose cone of a powerful all-round radar “Success-2A” with a review data repeater; an AP-114TS autopilot; a retractable landing gear; the absence of a bomb bay and an increased fuel reserve. The Ka-25C helicopter was capable of patrolling the water area at a distance of up to 200 km from the home ship, performing radar surveillance and target designation within a radius of 250 km, and providing retransmission within a radius of 250 km. And the same helicopter, converted into a search and rescue Ka-25PS, was equipped with an LPG-2 winch with a load capacity of 250 kg; searchlights mounted on the sides of the fuselage and an additional ARK-U2 radio compass.
Ka-25 helicopters were the first to receive Komsomolets of Ukraine anti-submarine ships (Project 61). Only one helicopter could be based on these ships, which solved a limited range of tasks. Project 1134 anti-submarine ships also carried one helicopter each. Project 1155 anti-submarine combat ships have already received 2 helicopters (Ka-25PL and Ka-25C), and in the second half of the 1960s, the Soviet Navy received Project 1123 anti-submarine cruisers “Moscow” and “Leningrad”, for which Ka-25 helicopters became the main anti-submarine weapon. In the future, they entered service and aircraft carriers of the “Kiev” type. Up to 20 helicopters could be based on each of them. Ka-25s were also used on Project 1143 anti-submarine cruisers and Project 1174 amphibious assault ships. Several Ka-25 helicopters have entered service with naval aviation units of the Border Guard service in the Far East.
Ka-25 helicopters were used for a long time in numerous sea and ocean campaigns of the Soviet Navy on warships of various purposes, both group and single-based. So, already in August 1968, Ka-25 helicopters on board the anti-submarine cruiser Moskva first entered combat service in the Mediterranean Sea. In June-November 1974, a group of 6 Ka-25BSHZ helicopters (towing cord charges) on board the anti-submarine cruiser Leningrad as part of the international forces took part in the mine clearance of the Gulf of Suez. In the 1970s and 1980s, Ka – 25PL helicopters were widely used from group-based ships (Projects 1123 and 1143) to search for NATO missile submarines in areas of their probable patrol.
In 1976, the modernized Ka-25PLS anti-submarine helicopter entered service with the Navy aviation. It was distinguished from the basic Ka-26PL helicopter by the new Strizh-K search and sighting system, in addition, its armament included a T-67 Strizh torpedo. In 1965 -1973, 460 Ka-25 helicopters in 18 different versions were manufactured at helicopter plant No. 99 in Ulan-Ude.