The first short-range Soviet guided air-to-ground missiles made it possible to significantly increase the strike capabilities of front-line aviation. Moreover, their use was associated with certain difficulties. In particular, the Kh-66 and Kh-23 missiles required the pilot to control the missile's flight until it hit the target. In addition, they carried a relatively light warhead, which is why they could not hit enemy fortifications, etc. objects. In 1970, the USSR Ministry of Defense initiated the development of a new guided aircraft munition that could effectively solve the assigned tasks, but would not inherit the shortcomings of its predecessors.
The project of a new guided missile was designated X-29. The development of this product was entrusted to the design bureau "Molniya" (now NPO "Molniya"), the chief designer was M. R. Bisnovat. Molniya's specialists completed most of the work, but in the mid-seventies they were forced to terminate their participation in the project. Due to the mass of orders under the Buran program, the Molniya Design Bureau transferred the documentation for the X-29 project to the Vympel Design Bureau (now the Vympel State Design Bureau). This organization already had extensive experience in the creation of guided weapons, including aircraft systems. Vympel employees under the leadership of A. L. Lyapin completed the development of the project and set up the serial production of new ammunition. At present, the production and support of X-29 missiles is carried out by the Tactical Missile Armament Corporation (KTRV), which includes the Vympel State Medical Design Bureau and other specialized organizations.
The existing guided missiles were aimed at the target with the direct participation of the pilot or aircraft automation. To simplify combat work, it was required to abandon radio command, etc. systems, creating new seeker, operating in the "fire-and-forget" mode. It was decided to equip the new X-29 product with a promising seeker that provides such an application. In view of the requirements for the launch range (up to 10-12 km), it became possible to equip the missile with an optical guidance system. As a result, they decided to make two modifications of the ammunition with the maximum degree of unification, equipped with different GOS - television and laser.
Unified units
For some reason, the Kh-29 missile received the same aerodynamic design as the previous guided weapons of this class - a duck. The rocket has a cylindrical body 3875 mm long and 400 mm in diameter. In the bow of the hull there is a set of X-shaped destabilizers, behind which are located rudders of a similar design with a span of 750 mm. X-shaped wings with aileron with a span of 1, 1 m are fixed on the tail part of the hull. Structurally, the hull is divided into five compartments that can accommodate this or that equipment. The homing head is located in the head, which is why the missiles of various modifications differ in the shape of the head fairing. A volume with a control system is located behind the head compartment. The middle part of the hull is occupied by a high-explosive fragmentation warhead, behind which a solid-propellant rocket engine is placed. The engine nozzle is located in the tail compartment, around which the aileron drives are located.
In the second compartment of the Kh-29 missile body there is a unified autopilot, which ensures the missile is kept on a given course and controls the rudders. It receives data from the used seeker and, on their basis, generates commands for steering machines. Ailerons on the wings are used for roll control. Two pairs of rudders are responsible for steering in the pitch and yaw channels. The rudders are connected in pairs (along the control channels) and are driven by two steering gears (one for each channel). When launched, the rudders are moved to a position that ensures the distance between the rocket and the carrier aircraft. The rocket electrical equipment includes a direct current ampoule battery with forced heating. To start and ensure the operation of the battery, a separate pyroblock is used that generates hot gas. The battery charge is sufficient to operate all systems for 40 seconds, which significantly exceeds the maximum possible flight duration.
The Kh-29 missiles are equipped with a PRD-280 solid-propellant engine with a thrust of up to 225-230 kN. Unlike the Kh-66, Kh-23 and Kh-25 missiles, the Kh-29 product has one engine nozzle located on the tail end of the hull. Such design differences are due to the lack of a full-fledged instrument compartment in the tail of the newer rocket body. The engine is started with a slight delay after uncoupling from the carrier aircraft, so that the hot gases of the engine do not damage the structure of the latter. The engine charge burns out in 3-6 s, accelerating the rocket to speeds of about 600 m / s. At the same time, the average flight speed, taking into account planning when uncoupling and gliding after the combustion of the solid fuel charge, is at the level of 300-350 m / s.
Guided missiles Kh-29 are equipped with an armor-piercing high-explosive warhead 9B63MN weighing 317 kg, which is about half of the starting weight of the product. The warhead is made in the form of a steel body weighing 201 kg, having a tapered head with thickened walls. Inside the case are 116 kg of explosive. The design of the warhead is calculated taking into account the need to defeat both manpower or unprotected equipment, and fortifications, buildings or ships. According to some reports, the design of the warhead can penetrate up to 3 m of soil and 1 m of concrete. In order to avoid a rebound when hit at sharp angles to the surface of the target, the warhead is equipped with an anti-ricochet device. The fuse of the KVU-63 warhead can work in contact mode or detonate with a slowdown. Contact sensors are located at the head of the rocket, next to the rudders, as well as on the leading edges of the wings. The fuse mode is selected by the pilot before starting. Contact blasting is designed to destroy equipment and manpower, and deceleration is used to attack bunkers, concrete structures, etc. objects.
The X-29 project initially provided for a modular design with the ability to install a homing head of the desired model. By order of the Ministry of Defense, employees of the Molniya Design Bureau, and then the Vympel Design Bureau, first developed two versions of the GOS: laser and television. The variant of the missile guided by reflected laser light received the designation Kh-29L or "Product 63", with a television head - Kh-29T or "Product 64". Externally, the missiles of these two types differ only in the shape of the nose fairing, inside which the homing head assemblies are located. At the same time, there is a slight difference in the starting weight of the products. The ready-to-use Kh-29L missile weighs 660 kg, the Kh-29T - 20 kg more.
Kh-29 missiles of both types were delivered in transport containers with dimensions of 4.5x0, 9x0, 86 m (Kh-29L) and 4, 35x0, 9x0, 86 m (Kh-29T). A missile with a laser seeker in a container weighs 1000 kg, with a television one - 1030 kg. Ejection devices AKU-58 and their modifications can be used for suspension on aircraft and for launching.
Homing heads
The head of the Kh-29L rocket has a shape formed by two conical surfaces, on which there are trapezoidal aerodynamic destabilizers that improve controllability and maneuverability in flight. A transparent section is provided in the head end of the fairing, through which the seeker “monitors” the laser illumination spot. In order to simplify the design and reduce the cost of production, the Kh-29L received a semi-active laser seeker of the 24N1 type, developed by the Geofizika Central Design Bureau under the leadership of D. M. Horola for the Kh-25 rocket. To carry out an attack, the carrier aircraft or ground gunner had to illuminate the selected target with a laser beam. The homing head in this case should detect the light reflected by the target and direct the missile using the proportional approach method.
The method of using a missile with a laser seeker depended on the type of onboard equipment of the carrier aircraft. So, in the case of the "Prozhektor-1" suspended container, which provided the movement of the laser beam only in the vertical plane, the rocket's automatics had to immediately work in the guidance mode with two-channel control. In the case of using more advanced systems "Kaira" or "Klen" with two-plane beam guidance, it became possible to climb to a certain height relative to the carrier aircraft and then perform a "slide" that increased the effectiveness of the attack when launched from low altitudes.
Depending on the type of lighting equipment used, the carrier aircraft, after dropping the missile, could perform maneuvering within certain limits. When using ground-based target designation equipment, the pilot, after launching, could leave the target area without risking falling under enemy anti-aircraft fire. The Kh-29L rocket could be launched at altitudes from 200 m to 5 km at a carrier speed of 600 to 1250 km / h. At the same time, the minimum firing range was 2 km, the maximum - up to 10 km. It should be noted that due to the use of a laser seeker, the actual firing range depended on meteorological conditions and other factors that interfere with the capture of the laser tag.
Homing head 24N1 of the Kh-29L missile
The use of the new autopilot in combination with the existing 24N1 laser homing head gave a very interesting result. The circular probable deviation of the Kh-25 missile, for which this seeker was created, reached 10 m. The new devices were able to bring the KVO of the Kh-29L missile to 3.5-4 m, which made it possible to hit targets marked with a laser with a high probability. Nevertheless, the real characteristics in the conditions of combat use could seriously differ from those indicated due to various technical and tactical reasons.
The Kh-29T air-to-ground missile received a more complex and expensive television homing head Tubus-2, created by NPO Impulse. Losing the product 24N1 in cost and simplicity, the Tubus-2 system simplified the attack of targets due to the full implementation of the “fire-and-forget” principle. When assembling the rocket, the television seeker is installed on the same mounts as the laser head of the Kh-29L rocket.
Homing head "Tubus-2" of the Kh-29T missile
GOS "Tubus-2" has a cylindrical body with a hemispherical head fairing made of transparent material. The head includes an optoelectronic part and a target coordinator mounted on a movable gimbal. In addition, equipment is provided for processing the video signal and transmitting data to the rocket autopilot. The video system of the "Tubus-2" product in the target search mode provides an overview of a zone with dimensions of 12 ° x16 °. In the automatic target tracking mode, the field of view is limited to angles of 2, 1 ° x2, 9 °. The coordinator is capable of tracking targets moving at an angular velocity of no more than 10 deg / s. The camcorder produces an image with a quality of 625 lines, 550 lines, 50 Hz.
The method of combat use of the Kh-29T missile is as follows. The pilot, visually or using onboard surveillance equipment, must detect the target and place it in the observation sector of the television seeker. Further, with the help of the rocket's video system, including the use of magnification, he must select a target and aim the aiming mark at it. To capture a target, the seeker “remembers” its features, such as a combination of contrasting light and dark areas. After reaching the permitted launch range, the pilot can unhook the rocket. The further flight of the rocket is carried out automatically. The rocket independently tracks the target and aims at it. Before the defeat, a "slide" is performed so that the missile can hit a target, for example, a fortified structure, from above, with the greatest efficiency.
Due to the maximum possible unification, the X-29 missiles have similar characteristics. The Kh-29T with a television seeker can be launched from an altitude of 200 m to 10 km at a flight speed of the carrier aircraft in the range of 600-1250 km / h. This provides firing at a range of 3 to 12 km. The circular probable deviation does not exceed 2-2.5 m. At the same time, the actual characteristics of the Kh-29T missile directly depend on various conditions and can vary within wide limits.
Kh-29T missile device: I - homing head: 1 - Granit-7T-M1 lens; 2 - television camera with vidicon; 3 - gyrostabilizer; 4 - blocks of the passive television target coordinator "Tubus-2"; 5 - destabilizer; 6 - power supply unit; II - control compartment: 7 - reaction contact sensors of the SKD-63 system; 8 - gas drives of rudders; 9 - steering surfaces; 10 - ampoule electric battery 8M-BA; 11 - electrical converter; 12 - control unit (equipment and filters); 13 - detachable plug connector; III - warhead: 14 - aluminum shells; 15 - steel body of the warhead 9B63MN; 16 - explosive warhead 9B63MN; 17 - front attachment point; 18 - detonators with safety-distance devices 3В45.01; IV - engine: 19 - switching unit of the contact explosive device KVU-63; 20 - UPD2-3 pyrotechnic cartridges for engine ignition; 21 - checks for starting the engine and KVU-63; 22 - igniter; 23 - PRD-280 solid fuel rocket engine; 24 - reaction cable contacts of the KVU-63 contact explosive device; 25 - wing; 26 - rear attachment point; 27 - gas generator of the gas supply unit; V - nozzle and tail unit: 28 - filters and pressure regulators of the gas supply unit; 29 - aileron; 30 - aileron drive; 31 - engine nozzle.
New modifications
The development of the X-29 project, begun at the Molniya Design Bureau, was completed by the Vympel Design Bureau. The same organization was involved in testing. At the end of the seventies, both proposed types of missiles passed the entire range of tests and the necessary refinements. In 1980, the Kh-29L and Kh-29T products were adopted by the Air Force of the Soviet Union.
In the course of the further development of the project, the Vympel ICB developed several new missiles that differ from the basic Kh-29L and Kh-29T in some parameters, the equipment used and the purpose. At the moment, the following modifications are known:
- UX-29. A training version of missiles designed for pilot training. It is an ordinary serial product with bright colors. Instead of the standard white, they are painted red (completely) or red with a white center section. When testing the Kh-29 missiles as part of the Su-24M bomber armament complex, a missile with a red head and tail section and a "checkerboard" red-and-white color of the central compartment was used;
- X-29ML. A missile with an updated laser guidance system, providing greater hitting accuracy;
- X-29TM. Upgraded version of the rocket with a new TV seeker;
- Kh-29TE. Upgraded export version of the Kh-29T. According to some reports, the firing range has been increased to 30 km;
- X-29TD. Modification with an updated guidance system. According to some reports, it is equipped with a television seeker with a thermal imaging channel, which ensures use at night;
- X-29MP. A missile with a passive radar homing head.
In arsenals
The Kh-29 missiles were put into service in 1980, after the outbreak of the war in Afghanistan. The first combat use of new ammunition took place only in 1987. Since April 87, Soviet pilots have regularly used such weapons against various complex targets. The use of optical guidance systems affected the effectiveness of missiles. So, in April 1987, the Su-25 attack aircraft of the 378th oshap, armed with Kh-25 and Kh-29L missiles, for the first time received an order to destroy the warehouses hewn in the rocks. For target illumination, aircraft systems "Klen-PS" were used. Due to the smoke generated during the attack, two of the four launched Kh-29Ls were unable to aim at the target. In addition, target illumination in combat conditions presented a certain difficulty.
To increase the effectiveness of the use of guided missiles in the 378th separate assault aviation regiment, with the assistance of specialists who came from the USSR, the so-called. BOMAN - "Fighting vehicle of the aircraft gunner". On the BTR-80, behind the turret, a rangefinder-designator "Klen-PS", taken from a decommissioned Su-25 attack aircraft, was installed. Later, a "modification" of BOMAN appeared, in which the target designator rangefinder could be removed inside the armored hull. To search for a target on such machines, an optical sight from the NSV-12, 7 machine gun was used.
The emergence of aircraft carrier vehicles soon affected the effectiveness of the use of guided aircraft weapons. When using this technique, attack pilots only had to go to the launch line, capture a target and launch missiles. The search and illumination of the target were assigned to the BOMAN crew, and the machine could do its job, being at a safe distance from the target. In addition, during combat work, the vehicle stood in one place and did not move, thanks to which the gunner was able to clearly and accurately highlight the selected target. When illuminated from an aircraft, the laser spot could be significantly displaced from the intended aiming point.
During the remaining years of the war in Afghanistan, Soviet pilots used about 140 guided missiles of several types. These weapons were mainly used to defeat protected complex targets, for example, warehouses, etc. objects in mountain caves. The characteristics of the laser seeker 24N1 made it possible to hit the rocket directly into the entrance to the cave. If there was an ammunition depot inside, then the 317-kilogram warhead of the Kh-29L missile left no chance for enemy supplies and manpower. In addition, they practiced shooting at the arch of the cave above the entrance when setting the fuse to detonate with a delay. Due to the high speed and strong body, the missile's warhead was buried in the stone and brought down the arch, locking the enemies and their property inside.
During the two wars in Chechnya, the Russian Air Force also made limited use of the Kh-29L and Kh-29T missiles. The relatively small number of missiles used was due to the difficult meteorological situation. Bad weather simply did not allow full use of all the capabilities of the guided weapon.
In the eighties, X-29 missiles began to be supplied to foreign countries. Such weapons were purchased at different times by Algeria, Bulgaria, Venezuela, East Germany, Iraq, Iran and other countries that acquired Soviet aviation equipment. In total, taking into account the former republics of the Soviet Union, missiles of the X-29 family have been used and remain in service in 26 countries.
Some foreign countries have had experience of using Soviet guided air-to-ground missiles. Iraq was the first foreign country to use X-29 missiles in battle during the war with Iran. Due to the presence of the enemy with a sufficiently developed air defense system, the Iranian air force was forced to actively use high-precision guided weapons, suitable for delivering strikes without entering the zone of destruction of enemy missiles. The carriers of the Kh-29L missiles were Soviet MiG-23BN and French-made Mirage F1 aircraft. The composition of the armament of the aircraft was also mixed, since they used both Soviet and French missiles. In addition, French laser equipment was used along with laser-guided missiles.
In the second half of 2000, during the Ethiopo-Eritrean conflict, the Ethiopian Air Force used Kh-29MP and Kh-29T missiles to suppress enemy air defenses. Su-25 aircraft, each of which carried two missiles with radar and television seeker, with fighter escort, were able to break through to the launch line and destroy the radar stations of the Eritrean Kvadrat air defense missile systems using the Kh-29MP. Further, the Kh-29T missiles “finished off” the remaining anti-aircraft systems. A little later, Ethiopia attempted a similar strike, but this time the enemy managed to detect the attack in time and launch anti-aircraft missiles, which damaged one of the enemy Su-25. Nevertheless, attack aircraft were able to destroy the air defense system radar, after which the "blinded" complexes were hit by free-fall fighter-bombers.
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The Kh-29 missiles can be considered a successful representative of Russian air-to-ground guided weapons. They have high guidance accuracy and great warhead power, allowing them to destroy various targets, including fortified buildings and underground structures. However, this weapon was not without its drawbacks. Laser and television guidance could only be carried out in good weather conditions, in the absence of artificial interference like smoke or various aerosols. In addition, over time, the short launch range, which was laid down in the requirements for the products, became insufficient to protect the aircraft from the later emerging small-radius air defense systems.
Although the Kh-29 missiles have both positive and negative features, they can be considered at least one of the most successful developments of their class created in our country. Moreover, at the time of their appearance and for some time after that, they were the most advanced domestic guided air-to-ground missiles.
