LCA Tejas :: The Bird That Gave Us Freedom

Monday, April 25, 2016

By Arya Bhatta

So , finally after a long time , the Tejas are ultimately being inducted into the Air Force with a sizeable order of 100+ jets on the Mk1 airframe [ 20 Mk1 + 80 Mk1A (may vary)] . Let’s take a while and look at its aspects in details and its past and future possibilities. I will deal the 2 topics separately.

The reason for DEVELOPING it

There was the need for an indigenous fighter jet felt as the nearly 250 Mig-21s were nearing their end of life and no suitable replacements were available. The American fighters couldn’t be thought of as cold war rivals and USSR jets had moved to advanced Su-30 generations and Mig-35 developments. Moreover Indian Govt wanted to develop a fighter, but In the early eighties, it was realized that no organization 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 1961. 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.

Design and technology


1st the design was a tailless delta which was later modified into compound delta configuration with a sweepback that was made reverse of Saab Draken. This reduces the drag, increases performances at supersonic, sub and transonic speeds. The low wing loading assures a high rate of climb, angle of attack and superior turning performance.

The most part of the airframe including the fuselage (doors and skins), wings (skin, spars and ribs), elevons, tailfin, rudder, air brakes and landing gear doors are of carbon composites. The use of CFC is highest among all available planes of its class giving it low weight but exceptional strength in spite of its small size. This helped in a 22% empty weight reduction and 40% reduction in parts required to assemble the entire airframe. [DOMESTICALLY DEVELOPED]

Flight Control

The plane has a RSS platform which helps it maintain a willful maneuverability by a 3D harmonic motion at a particular altitude. However such unstable aircrafts for safe operation need a FBW (fly by wire) system. The one developed for Tejas is a quadruplex one with 4 independent channels for flight data record and analysis by the DFCC (Data Flight Control Computer). It uses ada language and 32-64 bit microprocessors. [DOMESTICALLY DEVELOPED MOSTLY]


The avionics has a night vision goggles (allowing image in total darkness) compatible glass cockpit (moving from analog ones as thought first) . The display for this is a CSIR-CSIO HUD made by ADA and three 5 in x 5 in multi-function displays, two Smart Standby Display Units (SSDU), and a “get-you-home” panel providing the pilot with essential flight information in case of an emergency. However the Helmet Mounted Display and HOTAS systems are supplied by Elbit of Israel. Also the EL/M-2032 and EL/M-2052 fire control radars are supplied by Elta. There is a plan for Uttam AESA for Mk2 made indigenously. Tejas has dual GPS and inertial navigational systems with accurate RLG. The friend-foe identifier and high frequency radios are made by ADA and DRDO (IFF, VHF/UHF tech). The Electronic Warfare suite is made by DRDO and has radar-laser-missile approach warning systems with in-built jammers and EW countermeasure, towered array decoy. The suite has been named Mayavi. However, there are unconfirmed reports of the suite being developed by DRDO by reverse-engineering a few EW suites bought from Israel’s Elisra. However, the FLIR, IRST and dispenser pod and chaff pod have to be fitted externally.


Tejas is currently equipped with the General Electric F404-GE-F2J3 afterburning turbofan engine. The indigenous engine Kaveri failed 2004 tests in Russia after which DRDO and GTRE only backed off sighting some inherent design problems crept in from the very 1st stage. They wanted a new effort and afterwards a new effort is currently on as the K9 engine, which engineers are claiming to meet the 95 KN thrust for Tejas by 2019(approx.).

However, as seen the heart of the aircraft is US origin, which most of the other systems have Israeli links which are of foreign origin. The no of systems and subsystems developed in India can be clearly understood as opposed to random claims.

The project definition was over in 1988 while funding started from 1993. TD-1 came out on 1995 but due to problems completed its maiden flight in 2001. Till the US-India reproach before Civil Nuclear Deal, the project was plagued by sanctions and active technology denial. The timeframe don’t seem pale by those norms.

Now that India has made an admirable light-weight fighter, what can be the future?

To take any future course, a glimpse at the past can be helpful. The Marut jet designed by Kurt Tank, barely reached its full capacity due to engine problems (thanks to 1st nuclear tests) and ultimately faced extinction (read retired and thrown in garbage) merely serving 20 yrs as a bomber. Hence for our second attempt the full focus should be on K9 and K10 projects as soon as possible with ample fund and co-ordination.

The Mk2 version of a new airframe, larger is very promising and can be an ideal upgrade to the Mk1A after nearly 100 are produced. Faster production line of about 16-18 per year and Mk2 finalised demonstrator is required, as after that remains long series of testing by IAF. However, if Mk2 overshoots, one more sensible option can be to forget it altogether and proceed fully to the AMCA. If anyone thinks AMCA will have similar problems, it may be a biased thought for the “basic” requirements of a modern fighter lacked with no testing facility when Tejas was being made. However, that era gone, a bed for making a 4th gen jet exists right here in the country. The leap here has to be from 4th to 5th while for others it will be from 4++th to 5th. So, twin engine , super cruise , supermaneuvrability , are some essentials which have to made new over the existing and worked upon knowledge , prototypes in labs and facility . Plus stealth and avionics have to be upgraded significantly.

However, for my analysis Tejas was the most difficult project in aerospace defence India has ever worked upon or ever will in future. With a direct follow up project as AMCA, many engineers who had worked in LCA in DRDO / ADA have no more to do with Tejas, as HAL will now series produce, with minor upgrades and fits. They have moved on to the AMCA project or those who will retire will pass on the knowledge to next generation engineers. India was lucky to have a collective Govt-engineers-public firm collaboration who didn’t give up in tough times and times of isolation and loss of major partners (1991 USSR). They left a legacy – which we will apprize forever but yes, with a proper vision and mission.

Jai Hind!

– – – – – – – – – – – – – – –
This article has been written by Arya Bhatta exclusively for
Qualification : Class 12
Location : Kolkata