R-73 (AA-11) Short-Range Air-to-Air Missile

The PLA obtained the R-73 (AA-11 Archer) infrared-homing short-range air-to-air missile (SRAAM) as part of the weapon package for its Su-27 and Su-30MKK fighters acquired from Russia, making it the first air force in the Asia-Pacific region to be equipped with an all-aspect attack, helmet-mounted sight (HMS) guidance fourth-generation SRAAM. The R-73 has a wide off-boresight angle and exceptional aerodynamic performance, and is generally regarded more capable than most Western-designed SRAAM in current service.

The R-73/AA-11 SRAAM was first introduced in the 1980s by the Russian Vympel Design Bureau (now Spetztekhnika Vympel NPO) for the fourth-generation fighters of the Soviet Air Force such as the Su-27 and MiG-29. The missile uses a two stage nose canard design and thrust vectored exhaust to achieve turn rate performance well beyond established missiles such as the AIM-9L/M Sidewinder. The combined with an all-aspect IR seeker with a substantial off-boresight capability enables the missile to exploit engagement geometries. Because the missile has such high aerodynamic and seeker agility, the opponent would have little chance of defeating the missile through aggressive manoeuvre.

The Su-27 and Su-30MKK fighters are both equipped with helmet mounted sights (HMS) which allows the pilot to lock the missile on to a target well before the fighter's nose is "swung" to a position where the Air Intercept (AI) radar could lock up the target. A third generation missile such as the AIM-9L/M has an all-aspect seeker which is slaved to the fighter's radar, and therefore can only be locked on to what the radar can geometrically "see". The Su-27 and Su-30MKK would therefore get many and earlier firing opportunities if well flown.

The deployment of the R-73 missile and the Sukhoi Flanker series fighter provides the PLA with a combination of missile capability and airframe manoeuvrability, which would allow a competent pilot to get earlier firing opportunities, higher missile kill rates and better survivability against a Western fighter such as F-15 or F-16 fighter shooting a third generation missile such as AIM-9L/M Sidewinder. Additionally, the R-73 has an effective range of 300 metre to 30km (increased to 40km on later variants), and is capable of 12g manoeuvre, therefore allowing the maximum flexibility in using the missile for visual-range air combat.

Design

The R-73/AA-11 design features a canard aerodynamic configuration: control surfaces are positioned ahead of the wing at a distance from the centre of mass. The airframe consists of modular compartments accommodating the homing head, aerodynamic control surface drive system, autopilot, proximity fuse (radio or laser), 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 manoeuvrable 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 R-73 employs an "agile" gimballed seeker, believed to use a multiple detector cross array, capable of tracking targets at very large off boresight angles reported to be around 60 degrees, at high angular tracking rates. This enables the R-73 to be locked on to targets in an engagement geometry where an older missile cannot see the opponent. It also means that once the missile is fired, it can maintain its seeker locked on to its target despite violent manoeuvring which would force the target out of the seeker's field of view (FOV) with any older missile.

Specifications

Missile length: 2.90m
Missile diameter: 0.17m
Wingspan: 0.51m
Launch weight: 105kg (R-73M1), or 115kg (R-73M2)
Warhead: 7.4kg HE expanding rod warhead
Propulsion: One solid-propellant rocket motor
Off-Boresight Capability: +/-60 degree
Speed: Mach 2.5
G Limit: 40G
Range: 20km (R-73M1), or 30km (R-73M2)
Guidance: All-aspect infrared homing + helmet-mounted sight

Last update: 20 October 2008