2012年8月14日星期二

Tungsten Alloy Malitary and R-73 (AA-11) "ARCHER" Missile Family

The R-73 was developed to replace the earlier R-60 (AA-8 'Aphid') weapon for short-range use by Soviet fighter aircraft. The R-73 is an infrared-guided (heat-seeking) missile with a sensitive, cryogenic cooled seeker with a substantial 'off-boresight' capability: the seeker can "see" targets up to 45° off the missile's centerline. It can be linked to a helmet-mounted sight, allowing pilots to designate targets by looking at them. Minimumengagement range is about 300 meters, with maximum aerodynamic range of nearly 30 km (18.75 mi) at altitude.
The missile is used for engaging modern and future fighters, attack aircraft, bombers, helicopters, drones and cruise missiles, including those executing a maneuver with a g-force up to 12. It permits the platform to intercept a target from any direction, under any weather conditions, day or night, in the presence of natural interference and deliberate jamming. It realizes the "fire and forget" principle.
The missile design features a canard aerodynamic configuration: control surfaces are positioned ahead of the wing at a distance from the center of mass. The airframe consists of modular compartments accommodating the homing head, aerodynamic control surface drive system, autopilot, proximity fuze, warhead, engine, gas-dynamic control system and aileron drive system. The lifting surfaces have a small aspect ratio. Strakes are mounted ahead of the aerodynamic control surfaces. The combined aero-gas-dynamic control gives the R-73 highly maneuverable flight characteristics. During flight, yaw and pitch are controlled by four aerodynamic control surfaces connected in pairs and by just as many gas-dynamic spoilers (fins) installed at the nozzle end of the engine. Control with engine not operating is provided by aerodynamic control surfaces. Roll stabilization of the missile is maintained with the help of four mechanically interconnected ailerons mounted on the wings. Drives of all missile controls are gas, powered from a solid-propellant gas generator. The passive infrared homing head supports target lock-on before launch. Guidance to the predicted position is by the proportional navigation method.
The missile's combat equipment consists of an active proximity (radar or laser) fuze and impact fuze and a continuous-rod warhead. The engine operates on high-impulse solid propellant and has a high-tensile steel case. Russia's Vympel weapons designers have developed a one-of-a-kind air-to-air missile, which NATO has dubbed as AA-11, for use on foreign fighter planes. Techically and militarily the new missile, meant for quick-action dogfights, leave its foreign analogues far behind. Vympel experts have also made it possible for the new missile to be easily installed on all available types of aircraft. The AA-11 can also be used on older planes which will now be able to effectively handle the US' highly maneuverable F-15 and F-16 jets. The AA-11 missile is based on all-new components, use new high-energy solid fuel and an advanced guidance and control system which has made it possible to minimize their size. Their exceptionally high accuracy is ensured by the missile's main secret, the so-called transverse control engine, which rules out misses during the final approach trajectory. The transverse control engine is still without parallel in the world.
Russia has offered the export-version R-7EE air-to-air missile system for sale so that it can be fitted to foreign-made fighter aircraft. Developed by the Vympel state-sector engineering and design bureau, the R-7EE is designed for close-quarters aerial combat. Vympel specialists have developed a way of ensuring that the missile system can be fitted to virtually any type of aircraft. It can be fitted to older aircraft, which feature heavily in third-world countries' air forces. The R-73 ("Archer"/AA-11) third generation highly-maneuverable missile that has become the world's foremost IR guided dogfight missile. The Vympel R-73 is now operational with the MiG-23MLA (Flogger K) and all models of the MiG-29 (Fulcrum) and Su-27 (Flanker). All of these aircraft incorporate helmet mounted sighting systems. The R-73 has been designed to be fitted on new attack helicopter types such as the Mi-28 (Havoc) and the Ka-50 (Hokum). It is a lock-on before launch with gymbol limits exceeding 40° during acquisition and 70° off boresight after lock. It is of basic aluminum alloy construction (axial-symmetric cruciform scheme with small elongated tailfins) with the following component sections: seeker, aero-rudder actuators, autopilot, prox-fuze, warhead, solid-propellant motor, aero-surfaces, and thrust vectoring control vanes.

The unique combination aero and exhaust-gas maneuver control represents the world's first operational thrust vector missile providing an exceptional maneuver capability during the powered flight phase. Fixed stabilizers and AOA transducers are installed in the nose just aft of the seeker before fixed canard control surfaces. During the high impulse solid-rocket motor burn, the missile is controlled by the canards, joined in pairs on each control channel and by the four in-flow jet exhaust vanes which also work in pairs. The fixed tail-fins have ailerons on their trailing edges mechanically coupled to each other for roll stabilization. After motor burn out, and there is no indication of post boost cruise burn, missile control is provided only by the aerodynamic surfaces. All of the missiles gas actuators are feed by a power pressure accumulator that bleeds overboard and is estimated to be of a lower pressure then Western missiles due to reduced aerodynamic loadings on the optimized control surfaces. There is a 7.4 kg. (16.3 lbs.) rod-type warhead fitted with a dual active-radar proximity and contact fuze. The R-73 is fited to a common launcher rail that holds an internal cooling bottle.
The R-73 seeker is capable of being fired without any limitations of "G", "AOA", or aircraft attitude. The seeker-head can be cued to the target by matching the look angle of the locked up aircraft radar and/or IRST, or the sighting line of the pilot's eye through the helmet sight. Guidance to the intercept point is performed according to proportional navigation methods. The missile can engage targets maneuvering up to 12 G's. The minimum and maximum intercept ranges against non-maneuvering targets are published as 300 meters (984 feet) to 30 kilometers (16.4 NM). There has been a lot of press about a possible rear-firing air-to-air missile and Sukhoi released information about a reversed missile pylon for the R-27T ("Alamo B" AA-10b) IR short-burn version. The R-73 appears to have a better aero-chance because of its variable control exhaust jet vanes. Applications are being directed at bombers, transports, and deep strike aircraft.
The R-73 is a highly maneuverable missile that in many respects is believed to be superior to the United States AIM-9M Sidewinder, prompting the development of a more sophisticated AIM-9X now entering squadron service.From 1994 the R-73 has been upgraded in production to R-74EM standard (originally R-73M), which entered CIS service in 1997. The R-74EM has greater range and a wider seeker angle (to 60° off-boresight), as well as improved ECCM (resistance to countermeasures).

没有评论:

发表评论