The Buk (Russian: "Бук"; "beech" (tree), /bʊk/) is a family of self-propelled, medium-range surface-to-air missile systems developed by the Soviet Union and its successor state, the Russian Federation, and designed to counter cruise missiles, smart bombs and rotary-wing aircraft, and unmanned aerial vehicles.

[citation needed] With the integration of a new missile, the Buk-M1-2 and Buk-M2 systems also received a new NATO reporting name Grizzly and a new DoD designation SA-17.

[7] The modernisation improved the performance of the system radars, its "probability of kill" and its resistance to electronic countermeasures (ECM).

Additionally a digital target classification system was installed, relying on spectral analysis of returned radar signals.

Such sharing of the missile type caused a transition to a different GRAU designation, 9K317, which has been used independently for all later systems.

A further development of the system was unveiled as a concept at EURONAVAL 2004, a vertical launch variant of the 9M317, the 9M317ME, which is expected to be exported under the name "Shtil-1".

[16] This generation of Buk missile systems was stalled due to poor economic conditions after the fall of the Soviet Union.

[citation needed] The upgraded Buk-M3 TELAR will have a seven rollers tracked chassis and 6 missiles in launch tubes.

[18] The TELAR superstructure is a turret containing the fire control radar at the front and a launcher with four ready-to-fire missiles on top.

The TEL reload vehicle for the Buk battery resembles the TELAR, but instead of a radar they have a crane for the loading of missiles.

A self-propelled fire simulator installation JMA 9A317ET SAM "Buk-M2E", based on the mobile, is designed for training and evaluating the combat crew in the war environment to detect, capture, lock on to ("maintain") and defeat targets.

[citation needed] The system is estimated to have a 70% to 93% probability of destroying a targeted aircraft per missile launched (over 85% of Tomahawks in Syria).

A proximity fuse improves the "probability of kill" given the missile and target closure rates, which can be more than 3,000 km/h (1,900 mph) (or more than 900 m/s (3,000 ft/s)).

[24][25] With the use of the mobile command center Ranzhir or Ranzhir-M (GRAU designations 9S737, 9S737М) the Buk missile system allows creation of mixed groups of air defense forces, including Tor, Tunguska, Strela-10, and Igla.

[11] The Uragan uses the MR-750 Top Steer D/E band as a target acquisition radar (naval analogue of the 9S18 or 9S18M1) which has a maximum detection range of 300 km (190 mi) depending on the variant.

[32] The modernised version of the 3S90 is the 9K37M1-2 (or 9K317E) "Ezh", which carries the NATO reporting name "Grizzly" or SA-N-12 and the export designation "Shtil".

[35] The first Shtil-1 systems were installed into ships exported to India and China, specifically Talwar-class frigates and Type 052B destroyers.

The design had to conform to strict naval dimension limitations, allowing the missile to be adapted for the M-22 SAM system in the Soviet Navy.

In the forward compartment of the missile, a semi-active homing radar head (9E50, Russian: 9Э50, 9Э50М1), autopilot equipment, power source and warhead are located.

[citation needed] The 9M38 surface-to-air missile uses a two-mode solid-fuel rocket engine with total burn time of about 15 seconds; the combustion chamber is reinforced by metal.

The unified multi-functional 9M317 (export designation 9M317E) can be used to engage aerodynamic, ballistic, above-water and radio contrast targets from both land and sea.

It uses the inertial correction control system with semi-active radar homing, using the proportional navigation (PN) targeting method.

The lead developer, NIIP, reported the testing of the 9M317A missile within Buk-M1-2A "OKR Vskhod" (Sprout in English) in 2005.

This missile could increase the survival capability and firing performance of the Buk-M1-2A using its ability to hit targets over the horizon.

[36] The tail surfaces have a span of 0.82 m when deployed after the missile leaves the launch container by a spring mechanism.

Four gas-control vanes operating in the motor efflux turn the missile towards the required direction of flight.

SA-N-12 (export version) The HQ-16 is a medium range semi-active radar homing surface-to-air missile developed by the People's Republic of China.

[93] The probability of hitting targets one missile is: (data from the developer and several other sources) The minimum rs to 0.05 square meters.

Day-and-night passive optical system for target detection, thermal imager with minimal radiation (9А317 and 9А318).

[132] The "Viking" is reported to be able to operate both autonomously and in cooperation with other air defence systems, using their radar data for targeting, and have a gap of 20 seconds between stopping and launching missiles.