Since the fifties of the last century, the armed forces of the Soviet Union have mastered the latest helicopter technology, which could perform transport and some other tasks. In the course of the search for new methods of using new rotary-wing machines, the most original proposals appeared. Among other things, missile and helicopter systems were launched as part of a tactical missile with a launcher and a specially modified transport helicopter. One of the projects of such a system was designated 9K73.
The 9K73 missile and helicopter complex was supposed to be the development of the 9K72 tactical class system. The base model complex included the R-17 / 8K14 liquid-propellant rocket and several types of self-propelled launchers. Combat vehicles carrying missiles were able to move on roads and rough terrain, but in some cases their mobility and maneuverability were insufficient. Some areas that in theory could be used to place launch positions were inaccessible to the 9K72 self-propelled systems. For this reason, in the early sixties, a proposal appeared concerning a major change in mobility through the use of a non-standard vehicle.
Instead of a wheeled or tracked chassis, it was proposed to use a military transport helicopter with suitable characteristics as part of the new missile system. Its task was to transport a small launcher and a rocket on it. In this case, the missile system could be quickly deployed to the desired area, inaccessible to ground technology. Such capabilities could facilitate the delivery of strikes against some hard-to-reach enemy targets, as well as ensure their surprise.
Rocket and helicopter complex 9K73 in a combat-ready position. Photo Militaryrussia.ru
The development of the first version of the rocket and helicopter complex based on the 9K52 Luna-M system began in the first months of 1961. The result of this work was the 9K53 Luna-MV complex. At the beginning of February 62, a decree of the USSR Council of Ministers appeared, according to which a similar system should be developed based on the 9K72 complex with the R-17 rocket. The promising project was designated 9K73. The terms of reference required the development of a new version of the rocket called R-17V or 8K114 and a lightweight launcher 9P115. The Mi-6RVK transport helicopter was planned to be borrowed from the already developed Luna-MV project.
Several defense industry organizations were involved in the 9K73 project. The lead developer was OKB-235 (Votkinsk). The creation of a launcher of small dimensions was entrusted to the designers of GSKB (KBTM) under the leadership of L. T. Bykov. Also, a certain participation in the project was taken by OKB-329, headed by M. L. Milem, who developed the project of the helicopter-transporter of the missile complex.
The only element of a promising missile and helicopter complex that should have been developed from scratch was a self-propelled launcher. Several basic requirements were imposed on the 9P115 or VPU-01 product. It was supposed to ensure the transportation of the R-17V rocket in a horizontal position, including the delivery to the helicopter, loading into its cargo compartment and unloading. In this case, the movement had to be carried out independently and without the participation of tractors. In addition, on the 9P115 chassis, it was required to install a launcher necessary for launching missiles. Particular attention was paid to the dimensions of the self-propelled vehicle with the rocket: it had to fit into the dimensions of the cargo compartment of the Mi-6RVK helicopter.
As part of the 9K73 project, a new self-propelled launcher with a biaxial chassis was developed, which was equipped with a set of necessary equipment. The 9P115 machine had an elongated frame on which all the necessary units and systems were mounted. It provided for its own power plant and hydraulic transmission, which provided the possibility of independent movement. For maneuvering, the wheels of one of the axles were made steerable. It was assumed that after unloading from the helicopter, the self-propelled launcher would be able to independently reach the launch pad and prepare for firing there.
Rocket R-17. Photo Militaryrussia.ru
To keep the rocket in the correct position during transportation, as well as for its prelaunch rise to a vertical position, a special lifting ramp was introduced into the 9P115 equipment. This unit was a complex-shaped frame with a set of semicircular cradles for the rocket body. The ramp could swing on the rear axle using hydraulic drives, and thereby lift the rocket. Due to the need to reduce the dimensions of the entire system, the rocket in the stowed position was placed at the lowest possible height above the chassis. On the sides of it, on the sides of the chassis, there were several volumetric casings necessary to accommodate special equipment. Despite its small size, the 9P115 machine had to independently perform all operations to prepare the rocket for launch.
A launch pad with a set of additional devices was placed in the aft part of the chassis on a swinging base. All these units were probably borrowed from the 9P117 wheeled launcher and underwent some modifications associated with a different chassis design. In the case of a four-axle combat vehicle, the launch pad had the ability to rotate in a horizontal plane 80 ° to the right and left from the initial position. There was no vertical guidance due to the use of the appropriate equipment of the rocket itself. Directly under the tail of the rocket, on the launch pad, a reflector was placed, consisting of two parts and necessary to divert the reactive gases away from the vehicle.
The 9P115 self-propelled launcher had a full set of various units required for independent work at the launch site. She received a prelaunch service system, a special communication unit, an electrical and hydraulic system, topographic and control devices for rocket equipment, a set of spare parts, etc. When developing a complex of equipment, the developments on previous projects were taken into account, and also some existing components and assemblies were used.
For use by the 9K73 complex, the R-17V rocket was proposed, which was supposed to be a modified version of the basic R-17 / 8K14. It was a guided single-stage liquid-propellant ballistic missile. The rocket had a cylindrical body of large elongation with a tapered head fairing and stabilizers in the tail section. The head part of the hull was given for the placement of a warhead of the required type. Behind her was the hardware compartment. The central compartment of the hull was given over to large fuel tanks of the carrier type. The tail of the rocket housed the engine and some control systems. The body and tanks were made of steel and aluminum alloys.
Complex 9K72 in combat position. Photo Wikimedia Commons
In the tail part of the hull, a 9D21 liquid engine was mounted, using a TM-185 kerosene mixture and an AK-27I oxidizer as fuel. Also used was the starting fuel of the "Samin" type. Depending on some parameters, the engine thrust reached 13, 38 tons. The tanks held up to 822 kg of fuel and up to 2919 kg of oxidizer (at an air temperature of + 20 ° C). This fuel supply was enough to operate the engine for 48-90 s and pass the active flight section of the required length.
The R-17 rocket received an inertial control system necessary to improve the accuracy of hitting the target. To keep the rocket on the required trajectory, automation was used to track its position in space. In the active phase of the flight, it was possible to maneuver with the help of graphite gas rudders located behind the nozzle of the main engine. The range automaton took into account the longitudinal accelerations and determined the moment when the engine was turned off, after which the rocket had to continue moving along the required ballistic trajectory.
For the R-17 ballistic missile, several types of warheads have been developed. The main one was the high-explosive 8F44 weighing 987 kg with the possibility of detonation upon contact with the target or at a certain height above it. There was the possibility of using a special warhead 8F14 with a charge of 10 kt. Such a product had a mass of 989 kg and dimensions corresponding to the dimensions of a high-explosive warhead. Also, other versions of special warheads were developed. There were also several modifications of the chemical warhead with various combat equipment.
The total length of the R-17 rocket was 11, 164 m, the body diameter was 880 mm. The scope of the stabilizers was 1.81 m. The starting mass reached 5950 kg, of which up to 3786 kg fell on the supply of fuel, oxidizer and compressed air. In the first versions, the missile could attack targets at ranges from 50 to 240 km. Later, in the course of some modifications, the maximum range was increased to 300 km. The missiles of the first series had a circular probable deviation of 2 km. Later, this parameter was improved by half.
Launch pad of the 9P117 launcher of the 9K72 complex. Photo Wikimedia Commons
According to the existing project, the operation of the 9K73 missile and helicopter complex should have had several interesting features associated with the main ideas of the project. It was assumed that after installing the rocket, the 9P115 / VPU-01 machine would be able to independently approach the Mi-6RVK transport helicopter and, without additional help, enter its cargo compartment. After securing the missile system, the helicopter could rise into the air and take a course to the indicated area for firing.
The self-propelled launcher was supposed to leave the helicopter on its own and go to the required launch position. There, the forces of the calculation of the machine were preparing the complex for firing. Despite the smaller dimensions and other characteristic features of the 9P115 installation, the process of preparing the rocket for launch almost did not differ from the procedures performed in the case of other self-propelled carriers. The launch pad was being installed, onto which the rocket was raised using a ramp. Using the available equipment, the location of the launcher was determined and the data for guidance was calculated, after which data on the required flight range was entered into the automation of the rocket, and the launch pad was rotated to the desired angle. Upon completion of the preparation, it was possible to start using the remote control. After launching, the calculation had to transfer the launcher to the stowed position and return to the helicopter for evacuation.
The development of the 9K73 missile and helicopter complex project took about a year. After that, the design organizations handed over the necessary documentation to enterprises that were to start assembling prototypes of new technology. Already in 1963, the first and, according to some sources, the only prototype of the 9P115 self-propelled launcher, suitable for transportation by helicopters, was assembled. Soon after the completion of the assembly work, this product was sent for testing. In addition, a prototype of the Mi-6RVK helicopter, which had a set of special equipment for working with missile systems, was presented for testing.
During the tests, it was possible to identify some of the shortcomings of the missile system in its current form, which were quickly eliminated. After modifications, the systems of the 9K73 complex were again tested by various tests. Inspections of the launcher on the highways of the landfills, tests with a rocket, as well as tests using a full set of missile systems, including a helicopter, took a lot of time. It took about two years to check, fine-tune and other work.
Diagram of the elements of the rocket and helicopter complex. Figure Shirokorad A. B. "Atomic ram of the twentieth century"
Even at the testing stage, some problems were identified that could not be eliminated with the existing level of technology. At the same time, such shortcomings did not prevent the continuation of work on the complex. In 1965, the only sample of the 9K73 missile and helicopter complex was handed over to the troops for trial operation. The servicemen of the missile forces and artillery quickly mastered the new technology and began to test it in the conditions of army operation.
During trial operation, some of the conclusions drawn from the results of previous tests were confirmed. In addition, some not very successful features of the new development were again criticized. An analysis of the responses of the military allowed the command and leadership of the industry to draw conclusions about the real prospects of the original complex.
During all checks, the 9K73 complex confirmed the possibility of a quick transfer to hard-to-reach areas most suitable for launching missiles at certain enemy targets. In addition, the theoretical possibility of using such equipment in the close rear of the enemy, which additionally increased the range of the complex, was not ruled out. With all these advantages, the rocket and helicopter complex retained all the positive features of the 9K72 base system with the R-17 / 8K14 rocket.
Nevertheless, the 9K73 complex had some serious disadvantages that did not allow the existing advantages to be fully realized, as well as hindering the achievement of the required characteristics. For example, in practice, it was found that the Mi-6RVK helicopter, after installing the necessary equipment and with a launcher on board, loses in flight range, which reduces the real range of the rocket and helicopter complex.
Loading the 9P115 launcher with the R-17 rocket into the Mi-6RVK helicopter. Photo Militaryrussia.ru
Several disadvantages of the complex were associated with the small dimensions of the self-propelled launcher. The 9P115 machine could not carry the entire complex of necessary navigation and other equipment, which worsened the accuracy of determining its own coordinates with negative consequences for guiding the missile to the target. In addition, the reduction in the size of the machine led to the fact that it seriously lagged behind in terms of mobility from the full-size self-propelled launcher 9P117.
Another problem of the complex concerned the impossibility of using the full set of all the necessary equipment. For the most accurate target hitting, the battery of the 9K72 complexes needed data on the state of the atmosphere up to heights of about 60 km. Using information about the parameters of the wind at different heights, the calculations could make adjustments to the guidance of missiles and thereby increase the likelihood of hitting the target. To study the atmosphere, meteorologists of the missile forces should have used meteorological balloons and radar stations of several types. The meteorological battery of the missile brigade prepared a meteorological bulletin, which was then transmitted to the battalions and batteries.
Operating in hard-to-reach areas and at a great distance from other units, the rocket-helicopter complexes did not have the opportunity to use the data of full-fledged meteorological reconnaissance means. There was virtually no opportunity to introduce them into the rocket and helicopter complexes. For this reason, the calculations of the 9K73 complexes could not receive full-fledged data on the state of the atmosphere, which could negatively affect the accuracy of shooting.
Minor design flaws identified during testing and trial operation were almost completely corrected. Nevertheless, a number of characteristic disadvantages remained, getting rid of which was fundamentally impossible. At the same time, fatal shortcomings did not allow the 9K73 missile and helicopter complex to be operated with maximum efficiency. Because of this, the new system could not be adopted and put into production.
All elements of the 9K73 complex are deployed. Photo Aviaru.rf
According to various sources, the trial operation of the only 9K73 complex as part of the 9P115 self-propelled launcher and the Mi-6RVK helicopter continued until the early seventies. Despite the relatively long-term use, the new system was not considered as a possible means of rearmament of missile forces and artillery. The prototype of the complex remained in a single copy. After the resource was used up, it was written off as unnecessary and disposed of. A unique sample of military equipment has not survived to this day.
In the first half of the sixties of the last century, two missile-helicopter systems were developed in our country, using missiles of existing models. The 9K53 "Luna-MV" and 9K73 systems were tested and then entered into trial military operation, but they never made it to mass production and full-fledged use by the troops. During the inspections, it turned out that an original and interesting proposal regarding the transfer of missile systems by helicopters imposes serious restrictions on various characteristics of equipment and its design features, and, as a result, does not allow achieving the required results with the existing level of technology development.
The 9K53 and 9K73 missile and helicopter systems were the first and last developments in their class. After the unsuccessful completion of two projects, it was decided to abandon the further development of this direction. All subsequent domestic tactical missile systems were created without taking into account the possible joint operation with helicopters of different classes. This made it possible to develop projects with reasonable size and weight restrictions that do not interfere with the achievement of the required combat characteristics.
