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.
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:
- The Bharat Rakshak LCA Section. This is a treasure trove of information on the Tejas.
- Radiance of the Tejas (pdf) - An excellent article written by B Harry for the Vayu Aerospace Review. A must read.
- The Aeronautical Development Agency's Tejas Page.
- The LCA on globalsecurity.org
- The LCA Puzzle - Ravi Sharma.
- Tejas Gallery at Bharat Rakshak. There are many great pictures here.
- DRDO's Kaveri Engine Page.