AEW&C
India improving its AEW&C capability
Guy Martin / Johannesburg
All branches of the Indian military are undergoing massive expansion, and are purchasing new equipment at such a rate as to make India one of the world’s largest arms markets. Airborne early warning and control (AEW&C) aircraft are important force multipliers and these are being added to the mix as India attempts to keep one step ahead of its neighbours, notably China and Pakistan. It is taking a two-pronged approach by purchasing off-the-shelf AEW&C aircraft and developing and producing its own systems.
In the 1980s India ambitiously attempted to develop an indigenous AEW&C capability and in 1985 started its Airborne Surveillance Platform (ASP) programme, Project Guardian (later Airawat). A prototype flew in 1990 but the problematic project came to a halt in January 1999 when the Hawker Siddeley HS-748 testbed aircraft crashed, killing several important scientists and engineers. However, this was not the last of indigenous AEW&C development.
In April 2000 Russia sent two Beriev A-50 ‘Mainstay’ AEW&C aircraft to India, where they were used by the Indian Air Force (IAF) to evaluate the type and monitor Pakistani activity across the border. Although the IAF did not order the Russian A-50, it later made the decision to purchase the A-50 airframe with the Israel Aerospace Industries (IAI)/Elta Phalcon radar.
When IAI unveiled the Phalcon system at the 1987 Paris Airshow it was the first full-scale application of phased array technology in the world. It utilises an active electronically scanned array (AESA) L-band (D-band) Elta EL/M-2075 radar with antennas mounted in varying locations around the host aircraft to provide 360-degree coverage. The radar is fused with other sensors to give a complete picture of all the aircraft and emitters in the target area, and has a range of 380 to 400 km (235 to 250 miles) and the ability to track around 60 to 100 targets simultaneously.
IAI delivered an earlier model Boeing 707-based Condor variant to Chile, and created a small Conformal AEW version for use on the Gulfstream 550 for Israel and Singapore. In March 2004 the Indian Ministry of Defence agreed to purchase three Phalcon systems installed on Il-76 transports, at a total cost of US$1.5 billion.
The Phalcon-equipped aircraft are similar in appearance to Russia’s A-50 ‘Mainstay’, since they use a conventional (but non-rotating) radome mounted above the fuselage, containing three antennas that, combined, scan 360 degrees. Instead of the Soloviev D-30KP turbofans on standard Il-76s, India’s A-50EIs are powered by far more powerful Aviadvigatel PS-90 engines each developing 16 000 kg (35 300 lb) of thrust.
Deliveries of the A-50EI were scheduled for December 2007, September 2008 and March 2009, but the first aircraft only underwent maiden flight tests in November 2007. Deliveries took place in May 2009, March 2010 and December 2010 (although actual deliveries to India, rather than Israel, came months later). In spite of delays, it is likely that India will order another two A50EIs. Defence ministry sources say that there is, in principle, approval for two more Phalcons but that negotiations are still in progress.
Although India has the Phalcon AEW aircraft in service, it also wants a smaller aircraft to complement its larger AEW&C fleet and to carry a locally built radar developed in the follow-up to the Airavat project. In October 2004, India’s Cabinet Committee on Security cleared the Rs 1800 crore (US$398 million) indigenous AEW project. One of the main aims of the programme is to give local industry experience in developing surveillance and radar systems.
In February 2008 the IAF signed a US$250 million deal with Embraer for three EMB-145 radar platforms. Based on the ERJ 145 regional jet, the AEW aircraft features an in-flight refuelling probe, SATCOM capability, electronic support measures (ESM) equipment, increased electrical and cooling capabilities and various structural changes.
In place of the Erieye radar on the standard EMB-145 AEW&C aircraft, Indian aircraft will receive the Active Array Antenna Unit (AAAU) developed by the Defence Research & Development Organisation’s (DRDO’s) Centre for Airborne Systems (CABS). The S band (E-F band) active electronically scanned array radar should have a range of 250-375 km (155-230 miles) with 240 degrees of coverage. India will also supply the self protection system and communication systems and datalink. There are five operator consoles and seven crew rest seats inside the IAF’s EMB-145s.
A key factor in the deal is Embraer’s commitment to provide technical and engineering support during the development process. Under the agreement, Embraer will install the radar and associated electronics and will ensure the altered aircraft retain acceptable flight performance characteristics and handling. Furthermore, from January this year the CABS engaged EADS defence unit Cassidian to help with system integration and flight testing.
Embraer handed over the first EMB-145 at its factory in Brazil on February 21 and India will begin integrating locally produced equipment into the aircraft from July. Embraer will deliver the remaining two aircraft in 2012 and 2013. The EMB-145 will become operational with the IAF in two to three years time once testing and certification has been achieved, long past the originally scheduled date of 2011.
The Indian Air Force is said to be looking into acquiring another 20 airborne early warning platforms and in November last year the DRDO said it had received the go-ahead for developing another six AEW&C systems for delivery from 2015.
As airspace control is an important part the Indian Air Force’s duties, the IAF plans to set up five Integrated Air Command and Control System (IACCS) nodes across India, particularly along the regions facing Pakistan. It is integrating its AEW&C aircraft with various air control infrastructure, such as the Air Force Network. In addition, the IAF has put out tenders for a variety of radars and has bought dozens more, such as the Rohini, Arudhra and aerostat-mounted EL/M-2083.
The Indian Navy operates its own AEW&C aircraft in the form of Kamov Ka-31 helicopters. Following evaluation in 1996, four Ka-31s were ordered in August 1999, entering service in April 2003. Another batch of five, ordered in February 2001, was delivered in 2005. Total cost of the nine helicopters is estimated to be around US$200 million. Ka-31s are deployed from the INS Viraat aircraft carrier and three Talwar class guided missile frigates, as well as the Navy’s shore bases.
Based on the Ka-27, the Ka-31 features the E-801M Oko (Eye) pulse-Doppler phased array early warning radar. Typical range against a surface ship is around 100-200 km (60-125 miles) while the radar can monitor fighter sized aircraft at up to 150 km (95 miles). The radar can track 20-40 targets simultaneously, making it an important part of navy operations since surface vessels’ radar coverage is limited by the curvature of the earth.
The Ka-31’s six square metre (65 sq ft) antenna turns at 6 rpm beneath its fuselage and is folded against it when not in use. To prevent interference with the radar, the landing gear retracts. Once the operator has activated the radar and selected the operating mode, the system works automatically.
However, the Ka-31 has not lived up to the Indian Navy’s expectations. Its range and endurance are relatively short compared to fixed wing aircraft (loiter time is only 2.5 hours). Technical defects have also troubled the fleet, causing the grounding all nine aircraft around April 2006.
The Indian Navy is also seeking fixed wing aircraft, primarily to address the limitations of its rotary winged AEW&C aircraft and to equip the Vikrant class aircraft carrier (and possibly the Admiral Gorshkov aircraft carrier, which will join the Indian Navy as the INS Vikramaditya in 2013). In May last year India’s navy released a request for information (RFI) for four carrier-based AEW&C aircraft. Northrop Grumman responded by proposing its E-2D Advanced Hawkeye, which was cleared for export by the United States government. The US has previously – and unsuccessfully – offered the E-2C Hawkeye to India. While the first Vikrant class carrier will feature a ski-jump, the second vessel is likely to have a catapult system, allowing the E-2D to operate off its deck.
India’s rival Pakistan is also in the midst of acquiring AEW&C aircraft, after trying for more than 25 years. In June 2006 Pakistan signed a deal with Saab for four Erieye radar systems mounted on Saab 2000 turboprops. The Saab Microwave Systems PS-890 Erieye multi-mode pulse-Doppler radar can detect and track targets over sea and land at ranges of up to 450 km (280 miles) and amidst jamming, heavy radar clutter or low target altitudes operates out to 350 km (220 miles).
The Saab 2000 Erieye aircraft feature five operator stations and a HES-21 electronic warfare suite that includes laser, radar and missile approach warning sensors and countermeasures dispensers. Endurance is nearly ten hours. The first Saab 2000 arrived in Pakistan in December 2009 and so far three aircraft have been delivered, with the fourth set to arrive in June this year.
In a further sign of its strong relationship with China, Pakistan will receive four Shaanxi ZDK-03 AEW&C aircraft from its northern neighbour from the middle of this year. The aircraft are based on the Shaanxi Y-8/KJ-200 AEW&C turboprop aircraft but are designed to Pakistan’s specifications. The Pakistan Air Force’s first ZDK-03 was rolled out in November last year and all four aircraft are scheduled to be delivered this year. They feature AESA radars and open architecture electronics that allow for future improvements.