TEJAS The Illuminated Aircraft Of India

The HAL Tejas is India's very own aircraft. Designed by the Hindustan Aeronautics Limited and Aeronautical Development Agency. The Tejas is a single seater aircraft accompanied by a single jet engine. The Tejas aircraft is designed for the Indian Airforce and Indian Navy. The HAL Tejas came from a program named Light Combat Aircraft Programme which started around the 1980s. The need for the programme was to replace the aging MiG 21 Fighters. In the year 2003, the LCA programme was officially named as "Tejas".

The HAL Tejas

Tejas is a Sanskrit term that translates to 'fire' or 'illumination'. Tejas meaning a type of energy vitality or charisma.

Evolution Of The Tejas:

The Indian Airforce needed an Indian combat aircraft for two necessary reasons. The foremost reason was to replace the aging MiG 21 aircraft which were there since the 1970s. The other reason was to make the Indian Aircraft industry self-reliant. The IAF wanted an across-the-board advancement of India's domestic aerospace industry. In the year 1984, the Indian government formed Aeronautical Development Authority. The authority was established to carry out the LCA programme. While Tejas jets are considered as a product of HAL, the development credits go to ADA. The three goals of the program were:

The fly-by-wire flight control system, multi-mode Pulse-Doppler radar, and afterburning turbofan engine.

The project was commenced in the year 1987 in the month of October. The Dassault-Breguet Aviation was hired as a consultant for the designing. In the year 2005, Indian Airforce ordered 20 aircraft. This deal was followed by another 20 aircraft order. All the 40 Tejas jets were equipped with the F404-GE-IN20 engine. In December 2006 the "LCA Induction Team" was formed. The team consisted of 14 members working at Bangalore to prepare the Tejas aircraft for service. On 25 April 2007, the first series of Tejas aircraft LSP-1 were tested. The speed achieved by the jet was Mach 1.1. By the year 2009 Tejas aircraft completed 1,000 flight test and 530 hours of testing.

Single Seater HAL Tejas Aircraft

Design Of The Tejas:

The Tejas jet is a single seater aircraft. It features a tailless, compound delta wing. The jet is a single-engine multirole fighter aircraft. The prime focus of the aircraft to serve as an air superiority jet. The secondary motive was to perform ground attacks as well. The tailless, compound delta wing is designed so as to reduce the weight. The absence of control surfaces increases the area of external storage. This reduction also helps in better combat, high speed, and high alpha performance. As a result of extensive wind tunnel testing and CFD analysis, the aerodynamic configuration of the aircraft has been optimized. The optimization led to minimum supersonic drag, a low wing loading, and high rates of roll and pitch.

Airframe Structure:

The Tejas aircraft is composed of composite materials and lightweight alloys. Aluminium-lithium alloys, carbon-fiber composites, and titanium alloys are the material used in Tejas. The use of composite materials makes the jet 45% lighter airframe by weight and 95% reduction in surface area. The wings are manufactured from a single piece of carbon fiber polymer. The spars and ribs of the wing are also made of carbon composites. The evelons, tailfins, rudder, air brakes and landing gears use co-cured manufacturing technique. The radome is composed of Kevlar. The fin tip is made up of glass-fiber reinforced plastic. The usage of composite material makes Tejas both lightweight and strong at the same time. The Tejas also has few joints and rivets. This helps it be more reliable and less prone to fatigue. The tail fin is a honeycomb structure piece. It reduces the manufacturing cost by 80%. 

Composites Used In HAL Tejas

Avionics Installed:

The HAL Tejas aircraft has Night Vision Goggle compatible "glass cockpit". This cockpit allows the pilot to produce images of level flight in the dark as well. It also has a CSIR-CSIO domestically-developed HeadUp Display. The cockpit is also installed with 'get-you-home' panel which provides essential information to the pilot in case of an emergency. The information on the key flight systems and controls on a need to know basis is provided on the display panel. With the help of the multifunctional system, the pilot interacts with the onboard system. The hands-on-throttle-and-stick control is installed which reduces the workload of the pilot and increases situational awareness.

The EW(electronic warfare) suite is designed to enhance combat survivability during deep penetration. The EW suite is developed by Defence Avionics Research Establishment and Defence Electronics Research Laboratory. The suite is known as Mayavi.  It includes a Missile Approach Warning, Laser warning receiver system, self-protection jammer, chaff, jaff, and flare dispenser. 

The HAL Tejas aircraft is also equipped with an infra-red search attack track sensor. It can detect and track thermal energy emission. 

Flight Control System:

The HAL Tejas plane is equipped with quadruplex digital fly by wire flight control system. This system is used because of its statically stable design. The fly-by-wire control system makes pilot handling easy. The aerodynamic configuration of the Tejas is a delta wing design. It has a shoulder mounted wing configuration. The leading edge of the wing has three sectioned slats. The inboard section has additional slat to generate vortex lift over the inner wing. This also generated high energy airflow along the fin to enhance high angle of attack stability. The trailing edge of the wing has two segments of elevons(combination of elevators and ailerons). These provide pitch and roll control to the aircraft. The only empennage-mounted control surface is the single-piece rudder that provides yaw control to the aircraft.

Propulsion System:

The prototype of the Tejas was initially decided to have the General Electric F404-GE-F2J3 afterburning turbofan engine. The Gas Turbine Research Establishment launched a program to develop a domestic powerplant. It was named Kaveri. In the year 1988, after the nuclear tests conducted by India, The US stopped the sales of F404. The Tejas engine is an afterburning turbofan engine. In 2004, General Electronics was awarded a contract of  US$ 105 million. The contracted was of 17 uprated F404-GE-IN20 engines to power up the eight pre-produced Tejas LSP-1 aircraft. There were many difficulties faced in the manufacturing of Kaveri. Cost overrun and delays occurred in its development. Kaveri failed the high altitude test in Russia in the year 2004. This led to ruling out the powering of the first production of Tejas aircraft with Kaveri engines.

In 2006 ADA contracted Snecma to provide technical assistance to Kaveri. The DRDO considered of using the uprated Dassault Rafale's M88-2 Engine that provides a maximum thrust of 83-85 kN.

In the year 2008, it was found that a thrust of 95-100kN is needed to execute combat maneuvers with optimal weapon loads. Hence, there came a requirement of an in-production powerplant to be used. After evaluation and acceptance, the lowest bidder out of two Eurojet EJ200 and General Electric F414 chosen. The F414 emerged as the lowest bidder. The deal was finalized with an order of 99 GE F414 engines. The initial batch of the engine will be supplied directly by General Electric, and the remaining to be manufactured in India.

General Electric F404 during Testing

Operational History Of The Tejas:

In the year 2011, the first Tejas-equipped squadron was formed. The Tejas entered the service with No. 45 Squadron IAF (Flying Daggers). The squadron was initially based at Yelhanka Air Base Bangalore. Now the base has been transferred to Sulur Airforce Station in Coimbatore. The squadron will initially have 4 aircraft. 

The international debut of Tejas was made at the Bahrain International Air Show, in January 2016. Two Tejas Aircraft performed in this airshow.

On 21 November 2016, the Indian Defence Ministry said that they are proposing the export of Tejas. The deal and the pricing is being finalized with some friendly countries.

By the year 2024-25 the HAL said that it will export 123 Tejas aircraft to the Indian Airforce.

Specification Of The Tejas:

1. Length: 13.20 m
2. Wingspan: 8.20 m
3. Height: 4.40 m
4. Wing Area: 38.4 m(square)
5. Empty Weight: 6,560 kg
6. Gross Weight: 9,800 kg
7. Maximum Takeoff Weight: 13,500 kg
8. Internal Fuel Capacity: 2,458
9. Maximum Speed: Mach 1.8 (2,205 km/h)
10. Tejas Range: 850 km
11. Radius Combat: 500 km
12. Service Ceiling: 16,000 m
13. Wing Loading: 255 kg/m(square)
14. Thrust/Weight: 0.96
15. G-Limits: +8/-3.5g
16. Guns: 1 * mounted 23 mm twin barrel GSh-23 cannon.
17. Rockets: S-8 rocket pods (expected)
18. Missiles: 
• Air to Air Missile: Derby, R-73, Python-5(expected)
• Air-Surface Missile: Kh-59, DRDO Anti Radiation Missile.
• Anti Ship Missile: Kh-31, Kh-35( Both expected)
19. Bombs: Laser Guided, Glide Bombs, Cluster Weapons(expected).

Tejas, as its name suggests, is an illumination for Indian Aircraft Industry to the world.