After a laborious journey of 33 years, India’s Light Combat Aircraft (LCA) project which began in 1983, saw fruition in 2016. The aircraft was given the name ‘Tejas’, (Sanskrit “Radiance”), by India’s then Prime Minister, Shri Atal Bihari Vajpayee. It was indeed a proud moment for the Indian Air Force, as indeed it was for the whole country, when the first lot of two aircraft were flown in to form part of the newly resurrected 45 Squadron (The Flying Daggers) on 1 July 2016. This number will rise to ten by the end of the year, with overall procurement set to be 200 aircraft and 20 two seat trainers. When Group Captain Madhav Rangachari, IAF test pilot and the first Commanding Officer of the squadron, touched down flying the Tejas, his words captured the hopes and aspirations of the whole country. “I feel like I am on top of the world”, he said. “I feel honoured and privileged”.
The Tejas represents a quantum leap in India’s capacity to produce fighter aircraft. With its induction, the country has directly and indirectly bridged major technological gaps in several disciplines. Its induction comes almost 15 years after it first flew and 33 years after the project was taken up. The development cost of the fighter as given out in Parliament in February 2014 was Rs. 7,965 crore, including around Rs. 2500 crore for the Navy version, which is undergoing a few critical ship-based tests. While it is true that the project to manufacture the aircraft was beset with numerous time delays and cost overruns, it must be appreciated that building a modern fighter aircraft from scratch is no mean achievement. It redounds to the credit of all those involved in its development, that despite the numerous challenges along the way, they stoically persevered to deliver a world class product.Today, this indigenously designed 4.5 generation fighter aircraft has the potential to revolutionise the aviation sector in India, much akin to the impact Maruti had on the automobile sector in the eighties. The IAF has ordered 20 of them in the current IOC (Initial Operational Clearance) version and another 20 in the final, fully-ready condition. Sulur in Tamil Nadu has been chosen as the LCA base.
India felt the need to have its own indigenous fighter aircraft soon after independence, but lacked the capability. In 1969, Hindustan Aeronautics Limited was selected to develop a new multirole fighter airframe around a proven engine. The programme was however shelved shortly thereafter, for lack of a suitable power plant. A decade and a half later, in 1983, the LCA programme was taken up again with the primary purpose of finding a suitable replacement for the MiG 21 aircraft procured from the Soviet Union. At that time, the MiG 21, inducted in the late sixties, was the backbone of the IAF but the need for self reliance in this vital sector was paramount from the security point of view as also to propel India into the league of those countries that were major players in the aviation industry. The value of the aerospace “selfreliance” initiative was not simply the production of an aircraft, but also the building of a local industry capable of creating state-of-the-art products with commercial spin-offs for a global market. As military technology was advancing at a tremendous pace, India had to keep up with developments taking place across the world. The LCA programme was thus intended in part to further expand and advance India’s indigenous aerospace capabilities. The timing was right because given the average life cycle of a 2nd generation fighter aircraft to be 25 years, with another 10 to 15 years added with planned upgrades, the MiG-21s would have been due to be phased out by 2005. This gave a lead time of 20 years to DRDO/HAL to produce the LCA.
In the mid eighties, stocking of the IAF’s aircraft inventory required outside help, for the most part from the Soviet firms of Mikoyan and Sukhoi. India had by then, developed sufficient capacities to look into indigenous solutions for its military needs. To start the process, the Aeronautical Development Agency (ADA), consisting of a mix of over 100 manufacturing, academic and defence institutions, was founded in 1984 to oversee the LCA programme. This was necessary as no organisation existed which had the total capability to develop such an aircraft all on its own. The last time an indigenous fighter aircraft, the HF 24 flew was in 1971. Since then, the HF 24 assembly line had been shut down and the design team had been wound up. The only way left was to develop an aircraft from scratch.
ADA was critical to the development of new avionics, flight controls and various integrated onboard management systems. The Gas Turbine Research Establishment (GTRE), Bangalore, was tasked to produce the engine to power the new aircraft and it in turn began work on what would become the GTX-35VS ‘Kaveri’ after-burning turbofan. First flight was scheduled for 1990, with operational service to begin sometime in 1995.
A revision of the above timelines was necessitated as the IAF delivered its formal requirements to the design establishment only in October 1985. The plan to manufacture the LCA was thereafter officially finalised in1990 and covered the development in two phases. Phase one included proof of concept and first basic prototype. Phase two included refined prototypes and technology demonstrators. The first flight was completed in January 2001 and prototypes followed in 2003 through 2009. Till date, over 1500 sorties have
been recorded, without a single accident. This must rank as a stupendous achievement of all concerned. The complexity of manufacture can be gauged by the fact that a whole lot of institutions were involved in the manufacture of the Tejas. (See Figure: WORK CENTRES OF LCA PROGRAMME).
In phase 1 of technology demonstration, the focus was on ‘proof of concept’. It entailed the development and testing of two technology demonstrator aircraft. These aircraft were called TD-1 and TD-2. The decision to move forward was to be taken after the successful completion of this phase. This would be followed by the production of additional prototype vehicles. Overcoming various teething issues during this phase, TD-1 flew on 04 January 2001 with Wing Commander Rajiv Kothiyal on the controls. This was an important landmark for India as the last time an indigenous aircraft had got airborne on a first fight was almost 40 years ago on 17 June 1961.
Phase 2 involved additional testing and development of systems using Prototype Vehicles which would lead to the development of the final variant that would join the IAF and the Indian Navy. The first Prototype Vehicle, PV-1 flew on 25 November 2003. By 2005, the Tejas had proven itself in the testing phase and the first order for 20 Series Production aircrafts was placed. A follow on order for an additional 20 SP aircraft was placed in 2010.The planned product variants of the Tejas are the Tejas trainer and the LCA Navy. Tejas Trainer is a twoseat operational conversion trainer for the Indian Air Force. The LCA Navy comprises a twin- and single-seat carrier capable variant. The LCA’s naval variant is slated for deployment on the INS Vikramaditya as well as the Vikrant class aircraft carrier. It will be equipped for carrier operation with the capability to carry out ski-jump take-off and arrested landing. It will include strengthened airframe and landing gear and the nose is drooped for better cockpit vision, necessary for deck landing.
Tejas is a multi-role aircraft, designed to meet the tactical requirements of a modern air force and is perhaps the world’s smallest lightweight, multi-role, single engine tactical fighter aircraft capable of comprehensive air superiority and air defence roles. It weighs 8.5 tonnes and can carry three tonnes of weapons. To make the aircraft both lighter and stronger, upto 45 percent of its airframe is made of CFC materials, including in the fuselage (doors and skins), wings (skin, spars and ribs), elevons, tailfin, rudder, air brakes and landing gear doors. It is designed in an aerodynamically unstable tailless compound delta-wing configuration, optimised primarily for manoeuvrability and agility. While the Tejas’s Delta configuration has many advantages, the larger wing surface area causes increased drag and loss of energy in high speed turns. The large wing area however enables placement of six underwing hardpoints, three under each wing. One hardpoint is installed on the centre fuselage and another under the air intake on the port side to make for a total of eight hardpoints for carriage of precision guided munitions, missiles (air to air, air to ground, anti ship), rockets and bombs. They can also be used to carry equipment for electronic warfare, surveillance, drop tanks, etc. The large wing area also adds additional internal volume for fuel and avionics.
Cockpit. The Tejas’s advanced cockpit enhances the comfort level of the pilot. Its new generation glass cockpit is night vision compatible and makes for excellent forward, upward and side views. However, the canopy joins the fuselage spine and thus obstructs the rear view to an extent. The cockpit is fitted with Multi Function Displays (MFD), Head Up Display (HUD) and Stand by Instrumentation System driven by Open Architecture Mission and Display Computer for effective Human- Machine interface. Bharat Electronics developed its two 76mm×76mm colour liquid crystal MFDs, while the HUD was developed by the Central Scientific Instruments Organisation (CSIO) in Chandigarh. It has a liquid crystal returnto- home-base panel and keyboard, a helmet-mounted display and sight (HMDS), and its Hands-on Throttle and Stick (HOTAS) control system minimises pilot workload and maximises situational awareness. The aircraft has a highly reliable quadruplex digital fly-bywire Flight Control System. Its navigation suite includes Sagem SIGMA 95N ring laser gyroscope inertial navigation system (INS) with an integrated global positioning system (GPS). The communications suite includes VHF to UHF radio communications with builtin counter-countermeasures, air-to-air and air-to-ground data link, as well as a HAL identification friend-or-foe (IFF) interrogator. In addition, the cockpit includes an environmental control system developed by Spectrum Infotech of Bangalore. The avionics suite has an integrated utility health-monitoring system, ground proximity warning system, terrain referenced navigation system, instrument landing system, global positioning system, stores management system and three 1553B 32-bit mission computers. It is provided with Martin Baker (UK) zero-zero ejection seats. This will later be replaced by an Indian design. The advanced utility and health management system provides system health and warnings to the pilot through a Open Architecture Computer.
Weapons and Countermeasures. As mentioned earlier, the Tejas has eight external hardpoints. A 23mm twinbarrelled GSh-23 gun with a burst firing rate of 50 rounds a second and muzzle velocity of 715m a second is installed in a blister fairing under the starboard air intake. It carries the Elta 2032 Derby beyond-visual-range air-to-air missiles (BVR-AAM) from Rafael Advanced Defence Systems. These were weapon tested in the Pokhran ranges in 2011. it is also equipped with modern laser designator and targeting pods to hit ground targets. The aircraft’s electronic warfare suite, developed by the Advanced Systems Integration and Evaluation Organisation (ASIEO) of Bangalore, includes a radar warning receiver and jammer, laser warner, missile approach warner and chaff and flare dispenser. The multimode radar in the Tejas has been jointly developed by Electronics Research and Development Establishment and HAL. It incorporates multiple target search and track-whilescan and ground-mapping modes of operation. It includes pulse Doppler radar with Doppler beam shaping, moving target indication and look-up/ look-down capability. The radar is mounted in a Kevlar radome.
Tejas was originally planned to be powered by a new turbofan engine, the GTX-35VS Kaveri, to be developed by Gas Turbine Research Establishment. This could not meet the requirements of the Tejas and so the prototype development aircraft were fitted with General Electric F404-GE-F2J3 turbofan engines with afterburn. The production versions are fitted with one General Electric 85kN F404-GE-IN20 turbofan engine with full authority digital engine control. Development of the Kaveri engine is still a work in progress. As of now, the Tejas can fly at a maximum speed of 2,205km/h and at maximum altitude of 15,200m. The range of the aircraft is 3000km. Its service ceiling is 16,500m and weighs approximately 5,450kg, with a maximum take-off weight of 13,500kg. The upgraded version of Tejas, the Tejas 1A, with Active Electrically Scanned Array Radar, Unified Electronic Warfare Suite, mid-air refuelling capacity and advanced beyond the vision range missiles, will cost between Rs 275 crore and Rs 300 crore.
The Tejas proved its mettle when it participated for the first time in the international air show in Manama, Bahrain in January this year. Its performance was phenomenal, literally wowing the audience. Pakistan had also entered its JF-17 aircraft, made in collaboration with China, in the air show. After seeing the performance of the Tejas, it pulled out its JF 17 aircraft, from the air show, to obviate drawing unfavourable comparisons with the Tejas. In the show, Tejas pulled more than 8g, comparing favourably with the best aircraft in the world in its class. Finally, India has a state of the art aircraft which is indigenously designed and manufactured – truly a game changer which India can be proud of.
The Tejas is special, both because it is India’s fighter aircraft and because it compares well with the best in the world. It will galvanise India’s aviation sector, in a manner similar to the impact Maruti had on the automobile sector. There are many who choose to be critical, and who take sadistic pleasure in pointing to the delays in project completion, the huge cost overruns and the fact that the engine has to be imported as the Kaveri is yet a work in progress. But that does not take into account the sheer complexity of designing and manufacturing an aircraft of world standard from scratch. In any case, cooperation in such fields is the order of the day across the globe, as complex systems are much easier to produce with multiple stakeholders. India now has expertise in a field in which it had not yet entered. This needs to be carefully nurtured and supported to make India, in the years to come, a leader in Aviation and a name to reckon with. We now have a number of standard test facilities such as the LCA Mini Bird & Iron Bird for flight control system integration, a dynamic avionics integration rig, brake dynamometer & drop test rigs, secondary power system and fuel system test rigs, engine test bed, mobile electromagnetic interference/ compatibility test facility etc. All these were set up from scratch, but now we can build upon them for the future aircraft we will develop. This will most certainly be a boost for India’s programmes with respect to Advanced Medium Combat Aircraft; Unmanned Air Systems; Fifth Generation Fighter Aircraft and Medium Transport Aircraft. Indeed, after the ISRO’s space missions, Tejas represents the next big leap forward in the technological field. Its spin offs will transcend into other fields also, hopefully acting as a catalyst to revolutionise, in a true sense, India’s defence sector.
Acknowledgement. This article has been sourced primarily from the website of DRDO, airforce-technology.com, tejas.gov.in and defense-aerospace.com. Additional inputs for the article were provided by Air Marshal Sumit Mukerji, PVSM, SC, VSM, former AOC-in-C, Southern Air Command.