Akash E-SHORADS Explained: Part 2

The Akash E-SHORADS surface-to-air missile (SAM), developed by India’s Kanchanbagh-based Defence Research & Development Laboratory (DRDL), officially has no takers as yet. The Akash’s R & D project has been in existence for the past 20 years. Originally slated for completion within a 12-year period, the project’s Rs5 billion R & D phase had to extended by another eight years due to previously unforeseen technological and operational challenges, especially with regard to its fire-control and missile guidance systems. When the project took off in the late 1980s, the DRDL had proudly claimed that target engagement will be undertaken by the ground-based, active phased-array Rajendra L-band Battery-Level Radar (BLR) and a track-via-missile guidance system for the missile. However, the sheer technological challenges forced the DRDL to abandon this path by the mid-1990s, and the DRDO’s Bangalore-based Electronics R & D establishment (LRDE) instead took up the development of a passive phased-array variant of the Rajendra target engagement radar, whose laboratory version had 4,000 phase shifters, a spectrally pure travelling wave tube (TWT) transmitter (which at that time was imported from THALES Nederland), two-stage superheterodyne correlation receiver for three channels, a high-speed digital signal processor, real-time management computer, and a radar data processor. For the 25km-range missile the radio command-link guidance technique was adopted. It was this system that was until 2002 being proposed an all weather area air defence system for defending vulnerable areas (VA) and vulnerable points (VP) against manned airborne targets approaching from medium and high altitudes. The system has been designed to neutralise multiple airborne targets attacking from several directions simultaneously, and is fully autonomous in terms of its operation. The Akash E-SHORADS is now being offered in two versions: one whose launcher is mounted on the hull of a T-72M main battle tank (for the Indian Army), and another mounted on a cross-country truck built by TATA Motors, this being for the Indian Air Force (IAF). When deployed, the Akash comprises a network of early warning, tracking, and engagement radars and fire-direction control centres, all functioning in a network-centric manner. The system has advanced battlefield management software, which carries out relative threat computation and pairing of targets and missiles and missile fire-control. Dr R R Panyam has been the Project Director for Akash since 2002. About 1,000 scientists from 13 DRDO laboratories have contributed thus far to the Akash’s R & D effort.
During a series of test-firings in realistic desert terrain combat conditions last December, the complete Akash Weapon System was fielded and its mobility assessed. The user trials of intercepting unmanned flying targets were conducted between December 14 and 21, during which the Akash successfully intercepted its targets five times in a row in this campaign. The fifth and last trial successfully took place at 2.15pm on December 21 during which one missile destroyed a manoeuvring, turbojet-powered Lakshya aerial target drone. The ten-day long user’s trials saw the participation of 300 officials from the DRDO, DPSUs, and private industries. Dr Prahlada, who conceptualised the Akash Weapon System and headed the project for nearly for two decades and is currently the Chief Controller for R & D (Missiles) at DRDO HQ, provided the leadership during the recent test-firing campaign. In the aftermath of these trials, the following observations from the end-users’ perspectives are noteworthy:
1) By the time mobility trials of the Akash’s Army variant were conducted at Pokhran between June 11 and 29 last year, followed by flyover trials as part of the IAF-specific variant’s firing trials at Pokhran between November 15 and 17, and systems performance trials of the IAF-specific variant conducted at the Chandipur-on-sea-based Interim Test Range (ITR) near Balasore between December 14 and 21 last year, it emerged that while the Akash had the systems configuration and logistics tail of a medium-range SAM, it terms of mission effectiveness, it was no better than an enhanced short-range air defence system (E-SHORADS).
2) The missile’s engagement range of 25km has since early 2003 been viewed has highly deficient by both the IAF and the Indian Army, both of which have since insisted on a minimum range of 40km (and preferably 50km) if indeed the Akash is to be employed for protecting VAs and VPs against multiple attacks from cruise missiles. It is for this reason that both the Army and IAF have indicated that they will more likely opt for a land-based, road-mobile variant of the vertically-launched 70km-range Barak-2 SAM (using the S-band EL/M-2248 active phased-array radar for both target acquisition and engagement), unless the promised longer-range Akash Mk2 is made available as soon as possible. It is this factor that, according to the IAF and the Army, makes the Akash a financially unviable medium-range SAM when viewed from a techno-economic matrix. Therefore, unless the DRDL develops a 40km-range variant of the Akash, the system will have no takers, neither in India or abroad.
3) The Akash’s Battery-level configuration has not yet demonstrated its ability to simultaneously engage four airborne targets each with three missiles. Both the Army and the IAF are of the view that the Rajendra BLR, in order to ensure a 99.8% probability of successful target engagement against both manned combat aircraft and especially cruise missiles (to detect them, both the Army and Air Force are acquiring the ELTA Systems-built aerostat-mounted EL/M-2083 active phased-array radars), needs to morph into an AESA configuration, as opposed to its existing PESA design. Both the Army and IAF are of the view that it order to stay technologically relevant for combating future airborne threat scenarios, AESA-based target engagement radars are mandatory. The Army has also specified that such radars perform all search, identification, tracking, and engagement functions, instead of having three different radars for all functions ranging from target detection to tracking to engagement.
To address these requirements, the DRDL has already initiated R & D work on the Mk2 variant of the Akash missile, which will make use of a newer, higher-energy HTPB-based composite booster propellant housed within a slightly lengthened booster section. Its fuel-rich sustainer propellant, based on magnesium/sodium nitrate/naphthalene processed by pressure-moulding techniques, will remain the same. The Rajendra BLR’s modular AESA variant now being fabricated will include a carbon-fibre cover in front of the antenna array, RF distribution network, and about 80 transmit/receive modules (using hybrid MICs and MMICs for transmit and receive chains) that will be air-cooled. Each such module will comprise a power amplifier for the transmitted microwave signal, low-noise amplifiers as front-ends for the receiver channels, and phase shifters for accurate control of the signal phase in both transmit and receive modes. In the latter, amplification of the signal will be controlled as well. The phases and amplitudes will be continuously calibrated. Each T/R module will be connected to one vertical slotted waveguide. The technology for miniaturisation and mass industrial production of the T/R modules is believed to have been obtained from ELTA Systems since 1998, with the Indian recipients of such technologies being Astra Microwave Products Ltd, BEL and ECIL. Incidentally, such T/R modules were originally developed for the LRDE-developed long-range tracking radar (LRTR), whose design and performance parameters bear more than a close resemblance to the EL/M-2080 ground-based active phased-array L-band long-range tracking radar, two of which were supplied in late 2001 under a US$50 million order placed by the DRDO with the ELTA Systems Group subsidiary of Israel Aerospace Industries. For catering to the power supply requirements of the environmental control system of the Rajendra BLR’s AESA variant, the LRDE has selected Microturbo’s S20-G gas turbine-based APU, which weighs less than 80kg. It can easily be integrated into a compartment above the track passage of the T-72M. The S209-G runs on the same diesel fuel as the T-72M.—Prasun K. Sengupta