MiG-35 sensor suite unveiled.

The latest variant of the MiG-29 being offered to India features an AESA radar and a full suite of countermeasures

One of the highlights of the recent Acro India 2007 Exhibit in Bangalore, was the public unveiling of RSK MiG's MiG-35 fighter offering for the Indian Medium Multi-Role Combat Aircraft (MMRCA) competition. Though the airframe is the same well-known MiG-29M2 '154', virtually the entire electronic suite of the MiG-35 was on show for the first time. The aircraft avionics system has been integrated into the PrNK-35 fire control and navigation complex by the RPKB design bureau of Ramenskoye. All devices are interconnected by means of data buses compatible with Mil Std 1553B standard controlled by a computational system made by RPKB.

AESA radar

The main fire-control sensor of MiG-35 is the Zhuk-AE radar with active electronically scanned antenna (AESA) made by Phazotron-NIIR Corporation in Moscow. The mock-up of a preliminary variant of this radar was shown during the MAKS exhibition at Zhukovsky in August 2005. At that time, the radar featured a 700mm-diameter antenna comprising 1,088 transmit-receive (TR) modules (272 packs, each containing four modules); the antenna mirror was set at a 20[degrees] look-up angle. This design, however, turned out to be too heavy (450kg). In the next version the weight of individual components was reduced, cutouts were made in the radar body and a lighter magnesium alloy was introduced. Finally, the antenna diameter was reduced to 575mm and the number of T/R modules trimmed to 680 (170 packs of four modules each); the antenna itself was set in a vertical position. The overall radar weight was reduced to 220kg.

700MM ANTENNA WITH 1,000-1,100 T/R MODULES

This was the configuration adopted for the experimental Zhuk-AE radar (the original Zhuk-MAE designation has been dropped) produced near the end of the last year and installed on the prototype MiG-35 shown in Bangalore. The Zhuk-AE will start air tests from this March as the first Russian radar with active electronic scanning. Another prototype radar will start stand tests at the same time. For 2008, manufacturing of an initial batch of 12 Zhuk-AE radars is scheduled. The so-called "first stage" Zhuk-AE radar (also designated FGA29) shown in Bangalore is a modernised version of the mechanically scanned Zhuk-ME radar fitted with a new AESA antenna. It retains the existing computing system with data processor, signal processor and software, as well as the clock generator.

The Zhuk-AE/FGA29 radar can be produced by retrofitting the present Zhuk-ME radar. Phazotron will probably offer such an option for Zhuk-ME users such as Yemen, Eritrea, Algeria and India

The Zhuk-AE/FGA29 is a multifunction X-band radar (3cm wavelength), which can track and engage air, ground and naval targets. The radar in its present form has a search range of 130km against fighter aircraft (radar cross-section up to 5[m.sup.2]). According to Phazotron, by selecting the proper range between radiating elements, the antenna beam can be deflected by +/-60 degrees without parasitic side lobes. The radar can track up to 30 air targets and engage six of them simultaneously.

The "second stage" radar, designated Zhuk-AE/FGA35, will be fitted to the production MiG-35 fighter. It will receive a new computing system and new multifunction wideband generator. Thanks to this, the capabilities of AESA technology can be better exploited and new radar operation modes can be introduced. Thanks to the reduced size and weight of the radar modules, it was possible to move the antenna mirror back and therefore increase its diameter. The FGA35 will feature a 700mm-diameter antenna with 1,000-1,100 T/R modules (the present configuration comprises 1,064 modules, but slight changes are still possible). Phazotron-NIIR is now seeking the best method of heat dissipation--a critical issue for the success of future developments. The range of the Zhuk-AE/FGA35 radar will be 200km (for a 51112 target): the radar will be capable of tracking up to 60 air targets and engaging six of them.

Phazotron-NIIR designed and manufactured all radar components, except for the T/R module. In 2002, the Almaz-Phazotron subsidiary in Saratov tried unsuccessfully to produce its own T/R module. Phazotron-NIIR engaged two companies from Tomsk: Mikran and NII PP (Nauchno-Issledovatelskiy Institut Poluprovodnikovykh Priborov, Scientific Research Institute of Semiconductor Instruments) to produce the T/R modules. Mikran designs Russian monolithic microwave integrated circuits (MMICs) and TR modules, while NIIPP undertakes production on an industrial scale. One of the MMRCA tender requirements is the transfer of fighter production to India. Phazotron-NIIR is offering Indian companies a major share in future Zhuk-AE radar production.

Electro-optical locators

Other innovative features in the MiG-35 sensor suite are two electro-optical units--an air-to-air device (OLS-UEM) built into the aircraft nose and a podded air-to-ground device (OLS-K). Both units have been developed by NII PP institute (Precizionnogo Priborostroyeniya, Precision Instruments), a specialist in optical and laser equipment used for trajectory measurement in missile and space applications. The OLS devices represent the first application of the institute's technology in the aviation domain.

The OLS-UEM (Optiko-Lokatsionnaya Stantsiya, optical locator station) imaging infrared search and track device detects and tracks air and surface targets, as well as showing the pilot an image of the target for identification purposes. The unit includes a thermal imaging camera (with a 320x256 matrix) and a TV camera (640x480). The optical portion, including the scanning mirror, which is shared by both cameras, is housed in a transparent leucosapphire dome. The mirror scans a zone within [+ or -] 90[degrees] in azimuth and within -15[degrees]/+60[degrees] in elevation (with respect to the aircraft axis). Airborne targets can be detected at distances up to 45km in the tail-on position, or 15km in the head-on position.

The integrated laser rangefinder operates at two wavelengths: 1.57 microns (eye-safe) for training and 1.06 microns for combat. The rangefinder can determine the distance to the target from 200m to 20km. The weight of the whole unit is 78kg and the overall size is similar to the former OLS-29 electro-optical unit on the MiG-29 developed by UOMZ in Yekaterinburg. The prototype of the OLS-UEM locator was installed in 2006 on the MiG-29M2 experimental aircraft, subsequently transformed into the MiG-35 prototype. The same device, in the simpler OLS-UE version, is installed on Indian MiG-29K shipborne fighters.

Another electro-optical search-and-track device, OLS-K (Konteynernaya, podded), is used for detection and tracking of surface targets. According to Nil PP data, the OLS-K device can detect a tank from distance of 20km or a motor boat from 40km. The laser can measure the distance up to 20km. The optical channel, which is shared by the infrared sensor and the TV camera, is installed under a transparent dome similar to the dome of the OLSU-EM unit. The device also includes a laser rangefinder/target designator and laser spot tracker. The OLS-K is installed inside a conformal pod (length 1,980mm, weight 110kg) mounted under the starboard engine air duct.

Self-defence suite

The MiG-35 self-defence suite controls the warning devices (radar, optical and laser), electronic jammer and chaff/flare dispensers. This fully automatic system alerts the pilot to the threat, starts defensive measures and recommends an evasive manoeuvre. Urgent warnings are repeated in the form of vocal alerts.

The defintive configuration of the self-defence suite has not been fully specified. The most probable candidate among radar warning receivers is India's Tarang Mk2 unit, which is the standard equipment on Indian Air Force aircraft. The Russian option is the L150 Pastel unit. The radar warning receiver has three antennas: two of them (one on each wing tip) cover the front hemisphere, while the third, installed on the tailfin, provides 90[degrees]-azimuth coverage of the rear hemisphere.

The SOAR (Stantsiya Obnaruzheniya Atakuyushchikh Raket) infrared missile approach warning device was also developed by the NII PP institute. The device has two sensors; one of them, situated under the port engine air duct, scans the lower hemisphere, while the other, located on the top of the fuselage aft of the cockpit, watches the upper hemisphere. The SOAR can detect a Manpads missile launch from a distance of 10km, air-to-air missile from 30km and large antiaircraft missile from 50km. As well as detecting the missile launch, the device indicates the direction from which the missile is approaching.