Tejas - Conquering New Heights

By Anantha Narayanan K 13-Apr-2018


India’s indigenously developed Light Combat Aircraft (LCA) Tejas is all set to conquer new skies as the fighter aircraft is inching closer to achieving Final Operational Clearance (FOC) following the successful test-flights and hot refuelling trials. The latest updates from Aeronautical Development Agency tells that Tejas is all set to commence its Air-to-Air Refuelling (AAR) flight trials. Tejas is one of the best aircrafts in the Light Combat category. Dr. S Christopher, Secretary Defence R&D and Chairman, DRDO has recently said that the home-grown fighter has emerged among the best in class aircraft, providing flight stability even under extreme unstable conditions. Confirming Tejas’ air superiority, the Defence Minister Nirmala Sitharaman has said that the government preferred the induction of Tejas over foreign-made aircrafts for the Indian Air Force. She has further said that the production rate of Tejas will be increased to meet the IAF requirements.

Tejas is the smallest and lightest multi-role supersonic fighter aircraft of its class. It is designed and developed by the Aeronautical Development Agency (ADA) and Hindustan Aeronautics Limited (HAL) for the Indian Air Force and the Indian Navy. Tejas is an air-superiority fighter aircraft designed for air-to-air, air-to-ground and air-to-sea combat roles. This single engine, Compound Delta-Wing, Tailless Aircraft is designed and developed by ADA with HAL as the principal partner along with DRDO, CSIR, BEL, DGAQA, IAF & IN to meet diverse needs of the Indian Air Force (IAF) and Indian Navy (IN). The fighter is getting considerable upgradations and technological improvements ever since its induction into the IAF. HAL and ADA are constantly improving the systems and capabilities of the fighter.

Tejas has rules-based Artificial Intelligence incorporated into its Flight Control System (FCS). The FCS provides the pilot 'carefree handling'. The Mark-IA is an improved version of the original Mark-I featuring various upgrades including an advanced active electronically scanned array (AESA) radar system, a new electronic warfare sensor suite, and a new externally refuelling capability. ADA has been carrying out various tests regarding the AAR for the past few months which have been successful. All the simulated ground tests have been successfully completed as Tejas was refuelled by placing it at various attitudes. The technical integration for AAR has been completed and the trials were commenced on the ground. Tejas is expected to be ready for air-to-air refuelling by the end of April. Once Tejas achieves the operational aerial refuelling capability, it will help the fighter to extend its flight duration considerably.

The Indian Air Force (IAF) has issued a tender to HAL in December 2017 for the procurement of 83 Tejas Light Combat Aircraft including 73 single-engine Tejas LCA Mark-IA and 10 tandem two-seat LCA trainer aircraft. The IAF plans to induct a total of 123 Tejas Mark-IA, next to 40 Mark-I Tejas LCAs. HAL is currently increasing the production capacity from eight to 16 aircraft per year. As of December 2017, a total 20 IOC (initial operational configuration) aircrafts including 16 fighters and four trainers have been delivered by HAL to IAF till date according to a statement from the defence ministry. The production of remaining 15 IOC aircrafts (11 fighters + four trainers) are taken up at HAL. The production of 20 more Tejas LCA in the FOC configuration will begin following FOC clearance by India’s Aeronautical Development Agency (ADA), which is expected to be started in the coming months.

The approval of the FOC for the LCA will be a milestone achievement for ADA which has been entrusted with the responsibility of Design & Development of Light Combat Aircraft (LCA) by the Ministry of Defence.  Hindustan Aeronautics Ltd (HAL) is the Principal Partner, with major support from the Users (IAF & IN), DRDO, CEMILAC, DGAQA, CSIR, Other PSUs, Pvt. Enterprises and Academic Institutions. HAL is the Production agency building these aircraft. It has been a challenge for ADA and HAL when, the Tejas Programme was initiated to develop the technologies of a fourth-generation fighter aircraft for the Indian Air Force (IAF) and demonstrate them on two Technology Demonstrator (TD) aircraft about 25 years ago (1993). The Tejas team consisting of ADA, HAL, DRDO, CSIR, IAF, CEMILAC, DGAQA, PSUs, Private Industries and Academic Institutions have taken up the challenge and has flown the first Technology Demonstrator encompassing fourth generation technologies on January 4, 2001. Ever since then the project has been witnessing constant development till date with the IAF and Naval version of the aircraft getting several improvements.

ADA and HAL are gearing up to get the FOC of the LCA. Balance activities towards FOC, which will further enhance the operational capability of the aircraft are in progress currently. These include enhancement in the ‘g’ load capability, Air to Air Refuelling, additional weapon integration and gun integration. These are only capability enhancers and the IOC configuration aircraft itself is a potent weapon platform.

Technologies in Tejas

The Tejas aircraft has been incorporated with the advanced systems and technologies. Most of the technologies have been developed in parallel to the aircraft development itself.

  • Extensive use of composites in structure to an extent of about 90% by surface area and 45% by weight.
  • Advanced Avionics and Sensors: Open Architecture Computers (OAC) performing the Mission computer role with a robust plan for obsolescence management. The Stores Management System (For Weapons) has dedicated stores, data bus and enables easy role change.
  • The aircraft has an aerodynamically unstable configuration for enhanced manoeuvrability. The aircraft is controlled by a unique control law, allowing for high agility and carefree manoeuvring.
  • The aircraft has Quad Redundant Flyby-wire (FBW) Digital Flight Control Computer (DFCC) providing adequate levels of redundancy.
  • Carbon brake discs for efficient braking. f) High-pressure hydraulic system (4000 psi) to power the safety critical flight control system and other systems.
  • Robust computerised health monitoring of various utility systems.
  • Zero-Zero ejection seat.
  • Extensive test and simulation facilities for supporting design and development activities prior to actual flight tests Timelines of LCA AF Mk1.

HAL and ADA are also focusing on the Mk 1A version of the aircraft. Mk1A will have major improvements including better access to equipment and interchangeable panels, Air to Air refuelling, Internal Radar Warning Receiver (RWR) and external Self Protection Jammer (SPJ) Pod to enhance Survivability, AESA Radar, Capability to integrate different Beyond Visual Range (BVR) Missiles and Close Combat Missiles (CCM). ADA is focusing on the enhancement of the combat capabilities of the Mk 1A by integrating new weapons. It has already completed precision bombing with laser-guided 1,000lb bombs and unguided bombs. The integration of Rafael’s Derby fire-and-forget missile is in the final stage, and it will serve as Tejas’ initial medium range air-to-air armament. The integration of Active Electronically Scanning Array (AESA) radar is underway. The AESA radar will improve air-to-air superiority and strike missions and to achieve long detection ranges and multi-target tracking capabilities.

HAL has confirmed the order of 83 aircrafts of Mk 1A configuration in addition to the earlier 40 aircrafts. From the 124th aircraft onwards, LCA Mk II will enter service. It will be a bigger aircraft with a higher capacity engine, higher range and payload capacity, improved aerodynamics etc. The Mk II project is in the detail design stage. The Mk II is being designed to sport an array of upgraded weapons system along with all sensors and will be capable of carrying all futuristic indigenous weapons. The major thrust of the aircraft will be its ability to carry missiles like Astra and BrahMos. It will have Software Defined Radios (SDR) and all equipment to wage electronic warfare. The Mark II will be much superior in terms of its combat capabilities and will belong to the Medium weight class.

The naval version of Tejas is also expected to be ready for its operations from aircraft carriers. It has completely mastered the ski jump, take-off from aircraft carriers, both during day and night times. ADA is currently working on the arrested landing part of the aircraft, which is the most challenging part. The hook for the arrested landing has been integrated and ADA is progressing towards the demonstration. The Naval version of LCA Tejas is expected to prove its Carrier Compatibility by the end of the year.