Press & Media

Sosna: Air Defense Missile System (ADMS)

Oleg Korotkov– General Designer of Special Engineering, Doctor of Science, Academician of Russian Academy of Rocket and Artillery Sciences
Vladimir Ukleev– Discipline Head
Vladimir Kopylov– Head of Foreign Economic Relations Department

SAM 'Sosna'ADMS Strela-10 was developed by Nudelman Precision Engineering Bureau in the 70th and produced by Saratov Block Building Factory. The System has proved in troops as a highly effective, dependable and easy-to-operate armament.

The system was upgraded several times, has been made and delivered to tac¬tical air defense troops of Russian Armed Forces in sufficient amount and is itself one of the basic combat units on a tactical level of air defense.

A considerable amount of ADMS Strela-10 in various modifications has been delivered to the armies of more than 20 states in Middle East, Africa, Latin America and the Eastern Europe.
Now the development of ADMGS Pantsyr-S1 is completed and modernization of ADS Tor is done. These air defense systems distinguish themselves by high technological state of the art, availability of several firing channels and are capable to struggle against the wide range of air targets. However these systems are characterized by high complexity and high cost. They are also vulnerable for ARM because of radio-frequency radiation. Therefore as long ago as the nineties of the last century Arkady Shipunov, Academician of Russian Academy of Sciences has suggested developing a substitution for ADMS Strela-10 – it should be light, passive and rather inexpensive ADMS with an electro-optical control system and laser-guided SAM. This new system is intended for strengthening a tactical air defense and operation both independently and as a part of the composite air defense units. Nudelman Precision Engineering Design Bureau has continued its close cooperation with Saratov Block Building Factory.

By results of the carried out justifications the solution was accepted that the new perspective system, in comparison with ADS Strela-10M3, should possess qualitatively higher level of combat characteristics, namely:

• increase in combat range from 3 – 5 to 8 – 10 km;
• increase in ammunition load at a launching system from 4 to 12 SAMs;
• engagement not only airplanes, helicopters, UAVs and large cruise missiles, but also small-seized air attack weapons, including striking elements of high-precision weapon;
• almost completely automated combat performance cycle, including detection, taking for autotracking and missile guidance.

The export version of ADMS Strela-10 received the designation SOSNA.

Main principles of the system construction:

1. The system is based of new small-size highly effective air defense guided missile and new high-precision ECM-protected electro-optical control system (EOCS).
2. The missile is made as two-stage, with detachable engine and TV-guidance. The system incorporates the accumulated experience and modern approved technologies and has minimum overall dimensions and cost by ensuring a high efficiency. The missile is developed as maintenance-free and non checkable item.
3. The combined control system is used for missile guidance: a smoke-protected radio command system (on launching trajectory); high-precision ECM-protected laser beam guidance (after engine detachment and missile injection into a sight line).
4. High efficiency of missile is attained owing to high accuracy of guidance, use of specially developed two-section warhead with circular diagram of proximity fuse which overlaps the guidance errors, and also due to short flight times to the target.
5. High accuracy of SAM guidance is ensured due to minute errors of target tracking, high accuracy of laser-guidance system, large available lateral g-load of missile and due to application of special control algorithms realized in the microcomputer onboard a missile.
6. EOCS is developed as self-sufficient, with the necessary list of information channels, with own stabilization system, automatic guidance system and digital computer system.
7. EOCS could be used day/night and in adverse weather conditions owing to application of high-sensitivity thermal image channel that is not influenced by the fog and smoke. EOCS also can execute independent automatic sector search by zone scanning and can detect the targets by means of automatic control unit of target acquisition and tracking.

Engagement zones:
a) Helicopter AN-64 - 100 m/s c) Aircraft of F-16 type - 300 m/s
b) Aircraft of A-10 type - 200 m/s d) ALCM type cruise missile - 250 m/s 
Altitude, m
Heading Range, m
Advanced Thermal Imager

8. EOCS has increased jamming immunity due to using information channels with narrow fields of sight and application of special signals processing algorithms in the automatic control unit of target acquisition and tracking considering the target signatures. Besides, it is impossible to distort laser spot beam rider guidance or to flash an optoelectronic sensor of a flying missile by the similar laser beam.
9. The system can be used in automatic, inertial and semiautomatic laying modes. High automation of combat performance processes is attained owing to application of modern algorithms, and also due to information processing and decision making system, allowing to exclude the necessity of permanent operator participation in the fast flowing combat performance processes. In the semiautomatic mode which is used mainly in difficult counter measures environment the system is controlled by operator.
10. The missiles and EOCS are installed on the turning unit (mount) with gears for laying of two packages of missiles in containers. 12 SAMs are ready to launch and placed compactly enough on a launching mount owing to small weight and rather small overall dimensions of missiles.
11. The turning part is made as firing compartment which can be mounted on various carriers. In order to increase the crew safety and ensure the comfortable working environment and also to reduce overall dimensions and inertia moment of rotating part, the crew is arranged in the vehicle.
12. The combat vehicle of the system is equipped with modern precision toponavigation equipment and also set of data transceiving to the battery and regimental command posts.
13. The high concealment of the system is ensured by virtual absence of radio-frequency emission that is caused by EOCS application for from own EOCS in a mode of independent sector search. The radio channel is used within nearby two seconds only for missile guidance on a boost phase; for the subsequent guidance a laser beam is used. The data transceiving equipment of a combat vehicle used mainly for data receiving. Also the special coatings and constructive features are used to reduce thermal and specific signatures of a combat vehicle.
On the customer's requirement the system can be equipped with small-size acquisition radar.
SAM Sosna-R consists of main-propulsion stage, separated engine and detachment point. The SAM placed and stored in the transport-launching container (TLC) and launched from it. The missile has small acceleration time and is characterized by high aeroballistic efficiency.
The electro-optical system control (EOCS) ensures the target detection, automatic acquisition, tracking, measuring of angular coordinate and distance, and also laying of an information field of laser-beam control channel to the target at any time in the conditions of jamming and natural noise, including against the background of clouds, terrain features and horizon line.

Structure of EOCS:

1. Gyrostabilized platform where the following units are placed:
   • TV system;
   • thermal imaging channel;
   • laser range finder with beam deviation device;
   • equipment of missile control laser-beam channel;
   • thermal imaging channel of missile direction finder;
   • climate control device.
2. Digital computer
3. Control and display panel.
4. Automatic control unit for target acquisition and tracking.
5. Equipment of direction finder on a missile.
6. Analogue control unit.
7. Block of shaft-position encoders.
8. Power supply unit.

The system ensures large impact zones due to combination of high level of performances of missile and control system.

ADS Sosna can be used as a part of the battery, including the battery of mixed air defense unit, receiving target designation from a battery control post, from the commander's vehicle, or independently. Thus, the development of ADS Sosna will allow receiving a system with very high level of performances by acceptable level of expenditures. It is necessary to note that for the first time the system of this class will be capable to struggle effectively with wide range of high-precision strike weapons, and also to detect the targets in large sector and targeting SAM up to range of 10 km, not disclosing itself by radio-frequency radiation. Battery of SAM Sosna can use the sector search and thus can operate without external target designation, carrying out all-around surveillance and target designation in a passive mode that does impossible the attacks of antiradiation missiles.

Main characteristics of EOCS
operating modes automatic, semi-automatic, inertial
target detection external target designation, autonomous automated target sector search
range of guidance angles, deg
   azimuth ± 178
   elevation - 20... + 82
max angular velocity and acceleration, deg/s / deg/s2 50 / 150
field of vision, deg
   television system 2.0 х 3.0 / 6.5 х 9.0
   thermal imaging system 2.2 х 2.7 / 6.7 х 9.0
acquisition range (meteorogical optical range = 15 km, PH = 80%), km
airplanes / helicopters / cruise missiles / armour installations 16...30 / 10...14 / 8...12 / 8
measures distance, km up to 20
accuracy (MSE):
   stabilization, mrad 0.07
   finding of coordinates / distances, mrad/m 0.2 / 5.0
   lazer rangefinder guidance, mrad 0.1
laying of information field of lazer beam control channel, mrad 0.08... 0.12