Sunday, December 04, 2005


Before the flight of the Tejas (LCA, for those who choose to keep themselves uninformed) Prototype Vehicle – 2 (PV-2) on 2nd December 2005, quite a few defence enthusiasts, politicians, Air Force officers, and our media had virtually written off the project as a failure. Our newspapers and magazines were full of articles criticizing everyone from the management and the engineers to the sweeper boy. However, the flight of the PV-2 (Shown in the yellow primer in the picture) has proved that the Tejas project is very much alive and progressing at a steady pace. While there is no getting past the fact that the project has suffered from many delays and setbacks, it is far from being the white elephant that many want us to believe. Here, I will try to explain the significance of the LCA project and why it is necessary for the country. But first, some background information.

The Tejas is a supersonic multi-role aircraft meant to replace the IAF's frontline MiG-21 fighters. It is, as the name implies, the world’s smallest combat aircraft. It is constructed of aluminium-lithium alloys, carbon-fibre composites, and titanium. The aircraft features relaxed static stability with a full authority digital fly-by-wire system, which ensures excellent manoeuvrability, greater safely, and carefree handling. The delta wing ensures good performance at high altitudes and high speeds, while the radical low-sweep leading edge, optimised camber, and the fly-by-wire system ensure performance at high angles of attack. Other features include Multi-Mode Radar (air to air, air to ground, and air to sea modes), a glass cockpit, a Helmet Mounted target Designator, (HMD) and Hands on Throttle and stick (HOTAS) controls which reduce pilot workload. Powering the Tejas for the foreseeable future will be one General Electric GE F404-IN20 turbofan, while work on the indigenous ‘Kaveri’ GTX-35VS turbofan continues. The Aeronautical Development Agency (ADA) is the main developer, while Hindustan Aeronautics Limited (HAL) and the Defence Research and Development Organisation (DRDO) are major partners.

As of now, there are four Tejas in existence, viz. Technology Demonstrators – 1 and 2 (TD-1 and TD-2), and Prototype Vehicles – 1 and 2 (PV-1 and PV-2). The ADA has planned five prototypes (PV-1 to PV-5). PV-5 was originally meant to be a two-seat trainer, but this has now been advanced to PV-4. The Tejas first flew on 4th January 2001. As of Dec 2, 2005, 476 test flights were completed (TD-1: 166, TD-2: 200, PV-1: 109, PV-2: 1). Eventually, the LCA requires to fly 1,000 sorties to establish its Initial Operational Capability (IOC) which implies basic air-to-air and air-to-ground attack capabilities.

For all its capabilities, the Tejas project has suffered from a number of delays and has been plagued by many serious problems. The biggest of these is the Kaveri engine, which has been under development since 1986 at the Gas Turbine and Research Establishment (GTRE), Bangalore. The engine is too heavy, does not develop sufficient thrust, and there are problems with the fuel management system. While the engine has been sent to Russia for trials, it is unlikely to be seen on the Tejas anytime soon, and the American GE F404 will have to do. The Tejas’ Pulse Doppler Multi-Mode Radar (MMR), which will detect, track, terrain-map and deliver guided Beyond Visual Range (BVR) weapons, had also run into major hitches and, consequently, time and cost overruns. The option of using an off-the-shelf radar like the American AN/APG-67 or the Israeli Elta was being seriously looked at. However, the PV-2 has flown with an Indian MMR, which is a major milestone for Indian aviation. Many of these problems may be attributed to the economic sanctions imposed by the US after of nuclear tests in 1998. The supply of new engines, and the support for those already purchased was stopped. Also, the Flight Control System (FCS), which was being designed with the help of Lockheed Martin ran into major problems. Scientists working at Lockheed Martin were sent back; equipment, software and documents were impounded.

It is these events that have led to the labelling of the Tejas as a ‘dead project’ and a ‘damp squib’. In reality, nothing could be farther from the truth, as the flight of the PV-2 (a production spec aircraft) has proved. A project of this scale has seldom been undertaken by India. Air Marshal MSD Wollen, who was the Chairman of HAL from 1984 to 1988 says, “In the late eighties (and even now) India's aircraft industry was not as advanced as Sweden's, and yet India follows a more arduous design/development route for its Tejas, compared to Sweden for its JAS-39 Gripen. The Gripen makes use of a far higher percentage of off-the-shelf foreign technology, including the RM-12 engine (a license manufactured F404) and the mostly American weapon systems. Even the Chinese and Japanese projects make use of foreign engines: the Chinese JF-17 ‘Thunder’ uses a Russian Klimov RD-93 turbofan (an upgraded version of the RD-33 found on the MiG-29), while the Japanese F-2, itself an upgrade of the F-16, uses a General Electric F110-GE-129. On the other hand, India is developing its own engines and a few weapon systems (the Astra BVR air-to-air missile being the most significant). Hormuz Mama, in his article on the LCA in Flight International wrote, Combining a new airframe and engine puts development of the Tejas in the same class as the Dassault Rafale and Eurofighter Typhoon, according to ADA. Add to that the requirement to develop a naval variant, and the scale of India's undertaking becomes more evident. After the US imposed sanctions on India, Indian engineers and scientists designed and built a new quadruple-redundant, digital fly-by-wire flight control system from scratch – and that too in record time. Such a complex system is not the easiest thing in the world to develop, as is evident from the Chinese experience with the JF-17, which uses fly-by-wire only for yaw control (As much as they would hate to admit, developing a full-blown digital fly-by-wire system is simply beyond the capability of the Chinese). Moreover, the Tejas is one of the most structurally advanced aircraft ever built. Consider this: Carbon Fibre Composites used in the fuselage, wings, and tail account for 45% of the structural material used, aluminium alloys account for 43%, and titanium alloys 5%. The extensive use of composites, the small size, and the Y-shaped intake duct that hides the compressor faces make it one of the most (if not THE most) Low Observable (LO) 4th generation aircraft around.

Considering the in-house development of most of the Tejas’ components, the Tejas is, without doubt, one of the most indigenous aircraft around. Moreover, the Tejas program has spawned off some technologies, like the mission computer and the ‘Tarang’ Radar Warning Receiver (RWR) which are being used on many other IAF aircraft including the MiG-27, Jaguar, and Su-30MKI. To cancel the program now might ruin our fledgeling aerospace industry, whose very existence depends on the success of the Tejas and the Dhruv Advanced Light Helicopter. Look at what happened to the Canadian aircraft industry after they cancelled the promising CF-105 ‘Arrow’ interceptor in favour of the Bomarc Missile. As M Natarajan, chief executive of DRDO says, “After spending nearly Rs 10,000 crore between the Tejas and the Kaveri, the only way to go is forward.”

Some good reading material on the LCA:


BD said...

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Jaidev said...

when are you writing an update ?