Sukhoi Upgrade Poised For Takeoff
With Russia badly hit by western sanctions, HAL to develop new avionics for the fighters
Prasun K. Sengupta
The Indian Air Force’s (IAF) long-overdue project of undertaking a multi-phase deep upgrade of its 261 Sukhoi Su-30MKI heavy multi-role combat aircraft (H-MRCA), which was set to take off in 2013, is at last poised to begin following a decision by the IAF to undertake the bulk of the work locally at a cost of Rs 35,000 crore. The Hindustan Aeronautics Ltd (HAL) is taking the lead as prime industrial contractor.
The bulk of the upgrade work will involve the installation of new mission avionics on 85 Su-30MKIs initially, including the 50 that were procured off-the-shelf from Russia two decades ago. Of the 272 Su-30MKIs that have been procured to date, 11 have been lost to crashes thus far, with the remaining now serving with 12 squadrons. The IAF intends to place orders in the future with HAL for another 12 licence-assembled Su-30MKIs as attrition replacements. Since 2013, HAL has been undertaking maintenance, repair and overhaul work on those Su-30MKIs that had already attained their mid-life period of 1,000 flight-hours (also known as time-between overhauls).
Originally, it was envisaged by the IAF that systems integration of the mission-avionics suite—developed by the Defence Research and Development Organisation’s (DRDO) Bengaluru-based Defence Avionics Research Establishment (DARE) and HAL—would be undertaken by the Russia-based FSUE State Scientific Research Institute of Aviation Systems, or GosNIIAS, following which the Russia-based State Federal Unitary Enterprise Gromov Flight Research Institute at Zhukovsky will flight-test and certify the upgraded Super Su-30MKIs. HAL will next undertake avionics installation work at its Nashik facility.
But given the severe sanctions imposed by several Western countries and their allies in Southeast Asia and the Far East against Russia in the aftermath of Russia’s invasion of Ukraine, Russian military-technical and military-industrial entities have been hard-pressed to obtain microchip processors required for avionics, like the electronically scanned multi-mode radar (AESA-MMR) antennae that was to go on board the Super Su-30MKIs. Back in 2009, the Russia-based JSC V Tikhomirov Scientific Research Institute of Instrument Design had proposed its X-band AESA-MMR variant of the NO-11M ‘Bars’ (RLSu-30MK) PESA-MMR that currently equips the Su-30MKI.
As things now stand, the IAF wants HAL’s Mission & Combat Systems Research & Design Centre (MCSRDC) to become the systems integrator, and the DRDO’s Electronics Radar R&D Establishment (LRDE) to develop a customised variant of the indigenously developed ‘Uttam’ AESA-MMR (originally developed for the Tejas Mk.1A L-MRCA). Consequently, only the fire-control, weapons management and self-protection avionics suites will be upgraded (replacing Russian-origin hardware and software) using dual redundant MIL-STD-1553B databus-based architecture, along with MIL-STD-1760 stores (weapons) interfaces. The Su-30MKI’s data handling system (DHS) and digital flight-control computer for fly-by-wire flight-control, which use the GOST 26765.52-87 databus protocol (the Russian equivalent of MIL-STD-1553B), will be retained since Russia has not shared the source-codes of its DHS with the IAF and HAL.
The two principal elements of this new architecture are the HAL-developed open-architecture mission computer and display processor, followed by a digital map generator, which is required for presenting navigational cues when the aircraft cruises in terrain avoidance mode with the help of the AESA-MMR (this architecture has already been applied to the IAF’s 64 upgraded Jaguar IS/DARIN-3 interdictor/strike aircraft).
Other avionics due to go board include the HAL-developed solid-state data and video recording system, combined interrogator-transponder, SoftNet software-defined radio operating in VHF/UHF and L-band channels, upgraded TACAN, upgraded RAM-1700A radar altimeter, flight data transfer unit, a new-generation health and usage monitoring system (HUMS), upgraded VOR/ILS, modified Safran/Sagem Sigma-95N ring laser gyro-based inertial navigation system (RLG-INS) incorporating NavIC GPS navigation receiver, GPS splitter, a new infra-red search-and-track sensor, stores management system, blanking unit, flight data recorder, aviation clock, integrated standby instrument system, voice-activated command system for front cockpit, panoramic AMLCD cockpit displays supplied by SAMTEL-HAL Display Systems, MIL-STD-1760 stores interface boxes and pylon interface boxes. The tactical data-link will be the BNET-AR, supplied by Astra-RAFAEL Comsys Pvt Ltd, a joint venture between the Hyderabad-based Astra Microwave Products Ltd (AMPL) and Israel’s RAFAEL Advanced Defense Systems Ltd.
For self-protection, the Super Su-30MKIs will incorporate an internal suite that is a variant of the D-29 suite, which DARE had developed back in 2013 for the IAF’s MiG-29UPG M-MRCAs. Elements of this suite will include a unified receiver exciter processor (UREP) that encompasses a DARE-developed and MoD-owned Bharat Electronics Ltd (BEL) built Dhruti digital radar warning receiver (already retrofitted by Alpha Design Technologies on the Su-30MKIs under the IAF’s Project Eagle Eye, replacing the earlier BEL-built Tarang Mk.3 receivers), electronic support measures (ESM) and electronic countermeasures (ECM) elements, along with the ELT-568 mid-band (Ku and Ka bands) self-protection jammer transceivers imported from Italy-based Elettronica.
While the MoD-owned Bharat Dynamics Ltd will supply the DRDO-developed flare cartridges, the chaff cartridges will be supplied by the UK-based Chemring. For high-band (X-band) jamming, the Super Su-30MKI will be equipped with twin wingtip-mounted high-band jammers that have been developed by DARE and are being built by BEDL. DARE is now developing a belly-mounted low-band jamming pod for jamming hostile D-/E-band airspace surveillance radars. Also, to go on board will be the RAFAEL-developed X-Guard towed decoy system, which is also used by the IAF’s 36 Rafale M-MRCAs. Incidentally, the four IAF Su-30MKIs modified thus far to carry the BrahMos-A supersonic anti-ship missile already make use of the HAL-developed mission computers and weapons management computers, while Data Patterns Ltd has supplied the DRDO-developed fire-control system.
On August 26 this year, the DRDO formally completed the transfer of technology (ToT) to HAL for the production of the ‘Uttam’ AESA-MMR, that will first equip 44 Tejas Mk.1A L-MRCAs on order (the first 39 will use the EL/M-2052 AESA-MMRs supplied by Israel Aerospace Industries). According to HAL, it will take 48 months to develop a scaled-up ‘Uttam’ derivative for the Super Su-30MKI, with flight-tests slated to begin after 24 months of contract signature.
For DARE, the development of the six-unit dual-colour (ultra-violet and infra-red) missile approach warning system (DC-MAWS)—essential for all combat and combat-support platforms to provide hemispheric warning to pilots of incoming guided-missile attacks—has been a particularly daunting task. The MoD’s Defence Acquisition Council (DAC) had in September 2004 cleared the installation of DC-MAWS in 100 IAF aircraft (both fixed-wing and rotary-wing). DARE in January 2005 proposed to the IAF a project to design and develop DC-MAWS, jointly with the Israel’s Ministry of Defence and Elisra.
In July 2006 IAF accepted the proposal and in March 2008 agreed to install DC-MAWS on all its Su-30MKI H-MRCAs and projected an initial requirement of 50 DC-MAWS suites. In November 2008, the MoD accorded financial sanction for the development and integration of DC-MAWS on Su-30MKIs by DARE at a total cost of Rs.193 crore (including a foreign exchange component of Rs 172 crore), with a project date completion (PDC) of 55 months (June 2013) under the mission-mode (MM) category.
On July 17, 2006, Cassidian, the defence and security division of the European EADS, and the MoD inked a contract for procuring a small number of MILDS AN/AAR-60 DC-MAWS. This MoD move came despite DARE signing a memorandum of understanding with Cassidian on the joint development of an initial 36 DC-MAWS suites for both fixed-wing and rotary-winged aircraft of the IAF and the Army Aviation Corps that made use of the MILDS AN/AAR-60 system with a planned initial operational capability for 2007. The agreement also included the co-production of these suites by BEL. In December 2008, DARE signed a tripartite USD 37 million (Rs 148 crore) contract with Israel’s MoD and Elisra (now owned by Elbit Systems) for the joint development of a DC-MAWS suite with a projected PDC of 48 months (December 2012). The scope of the contract included delivery of six sensors for one DC-MAWS suite. HAL was selected by both the IAF and DARE as the nodal agency for structural modification of Su-30MKI airframes for integration of the DC-MAWS suite.
Subsequently, DARE found out that the sensors (that make up the DC-MAWS suite) submitted by Elisra were heavier and bigger in dimension (24cm in height and 4kg in weight). In May 2009 DARE informed Elisra that the sensors might not be accepted for the Su-30MKIs as it would cause serious restriction on their flight envelopes. The IAF too expressed the same view in March 2010. But Elisra in June 2010 expressed its inability to make any significant weight reductions. The installation of the six sensors on the Su-30MKI was not cleared in December 2012 by an expert committee at locations specified by DARE, as it would involve cutting the aircraft’s internal structure and the destruction of internal thermal masking coatings.
Subsequently, the committee in January 2013 cleared the installation of only four DC-sensors with a limitation of only 15-degree angle-of-attack (as against the Su-30MKI’s capability of 90 degrees). In February 2013, DARE approached the Su-30MKI’s OEM (OKB Sukhoi and IRKUT Corp) for expert review and clearance of the proposal for aircraft modification to integrate DC-MAWS sensors. In May 2013, the OEM clarified that the integration of DC MAWS sensors would significantly affect the Su-30MKI’s flight performance since the DARE-recommended installation locations were highly sub-optimal.
In December 2011 the project cost was subsequently enhanced to Rs 228.80 crore because of exchange rate variation (ERV). This was further increased to Rs 273.80 crore in July 2013. The MoD also extended in July 2013 the PDC of the project by 24 months (up to June 2015). A Comptroller & Auditor-General (CAG) audit in October 2014 observed that though the increase in the weight of the DC-sensors was a cause of concern to the IAF as well as DARE, the sensors (four for each aircraft, instead of the originally envisaged six) were accepted with their present weights. With this the possibility of adverse effects on the Su-30MKI’s flight envelope remained.
In response to audit observations regarding delays in the development of the DC-MAWS suite and its operational impact, DARE in January 2015 agreed that the performance parameters of the DC-MAWS on Su-30MKIs would be limited. It further added that the DC-MAWS requirement on Su-30MKIs was not originally envisaged by the IAF and hence DARE executed it as only a technology demonstration (TD) project, instead of MM project and the project was wrongly categorised as MM.
Subsequently, DARE relocated the installation of DC-sensors on the Su-30MKI to the satisfaction of the IAF and the expert committee, which concurred in February 2015 that the installation of all six sensors was imperative. Between March and April 2015, Elisra delivered all the six DC-sensors only after the completion of factory acceptance tests (FAT). The flight evaluation of DC-MAWS was also carried out between March and April 2015 on an Elisra-owned Cheyenne airborne testbed. An amount of Rs 194.16 crore had by then been incurred on the project by March 2015. The IAF stated in April 2015 that flight-trials of DC-MAWS on a Su-30MKI were expected to commence in December 2015.
The CAG audit also observed in June 2015 that in order to meet the latest PDC (June 2015) of the project, DARE, after development and testing of the DC-MAWS suite on an airborne testbed, closed the project claiming it to be successful. In order to prove the developed DC-MAWS suite on a Su-30MKI, DARE had proposed in June 2015 to take up a separate project. DARE further stated that the delay in development was because of time taken (from February 2012 to February 2015) by the IAF to assess the impact on aerodynamics of the Su-30MKI.
In response to the draft report of April 2015, the DRDO reiterated in June 2015 the views of DARE that the DC-MAWS project was taken up as a TD effort and suggested to exclude the project from its draft report. The replies may be seen in the light of the fact that the IAF had clearly projected back in March 2008 the requirement of the DC-MAWS suite for Su-30MKIs and accordingly, the project was sanctioned under the MM category. Also, neither the DRDO nor DARE took any initiative during the developmental phase to obtain an amendment to transition from the project from the MM to TD category. Further, flight evaluations of the developed DC-MAWS suite were carried out on a Cheyenne airborne testbed and as such, the success or otherwise of DC-MAWS with oversized sensors, would be known only after flight evaluation on modified Su-30MKIs, for which a separate sanction was awaited. Till then, the IAF’s Su-30MKI fleet would have had to operate without DC-MAWS capability.
In 2016, DARE once again succeeded in resuscitating the DC-MAWS project by proposing to install four DC-sensors to the fore and aft of each of the two Interface Beam Assemblies (one under each outboard wing pylon), with the remaining two sensors being mounted on the topside and belly of the Su-30MKI airframe. But such a configuration too has not yet been approved by OKB Sukhoi, which instead has cleared the MILDS-A installation configuration that had been proposed by the industrial partnership of Hensoldt (which bought over Cassidian), BEL and Alpha Design Technologies back in 2016 itself.
As a consequence of this, DARE has developed a DC-MAWS suite installation package that does not have the support of OKB Sukhoi and will therefore be regarded as an unauthorised and non-certified fitment, which in turn will lead to both OKB Sukhoi and IRKUT Corp withdrawing their airworthiness certifications for all such modified Su-30MKIs. The total product liability, therefore, will rest squarely on the shoulders of DARE and HAL, with devastating consequences for the IAF and its entire Su-30MKI fleet.
Instead, what the IAF should have done in the previous decade was to go for the very same certified DC-MAWS fitment configuration that was specified by OKB Sukhoi for the 18 Su-30MKMs of Malaysia that were delivered between 2007 and 2009. This would then have become a win-win solution for all the involved parties (Russian and Indian) and could well have generated similar solutions for the IAF’s upgraded MiG-29UPGs. Instead, the evident criminal negligence displayed by the MoD, DRDO and DARE since the previous decade has only ensured that the IAF’s MiG-29UPG and Su-30MKI fleets remain devoid of DC-MAWS fitments to this day.