Explained: How New Tejas Fighter Jet Variant Is Different From Its Predecessor

The upgraded version of the indigenous supersonic fighter aircraft, the Tejas Mk1A, is expected to be delivered to the Indian Air Force by July, reports said. The LCA Tejas Mk1A, the advanced version of the Mk1, conducted its first successful test flight on March 28 this year, marking a historic moment in India's fighter jet development programme.

The Light Combat Aircraft (LCA) programme was envisioned in the late 1980s to replace the MiG-21 and Su-7 fleet. The programme got a boost in the late 90s and on January 4, 2001, the Technology Demonstrator-1 (TD-1) version of the LCA was airborne and rechristened 'Tejas', a significant moment in the Indian Air Force's history.

The Second Series Production (SP2) Tejas aircraft was given initial operational clearance in 2016. The Tejas Mk1 version was inducted in the Air Force's No. 45 Squadron - 'The Flying Daggers'. Later, another Tejas squadron, the No. 18 Squadron - 'The Flying Bullets' began operating the Mk1 variant.

How Is Tejas Mk1A Different?

The Indian Air Force has ordered 83 Tejas Mk1A variants in a Rs 36,468 crore deal with Hindustan Aeronautics Limited. In November last year, the Defence Acquisition Council cleared the project to acquire 97 more Tejas jets for the Indian Air Force.

On March 28, Group Captain KK Venugopal (Retired), a test pilot, took the Tejas Mk1A to the skies and was airborne for 15 minutes. The sortie was the first successful flight of the MK1A version of the fighter jet.

Group Captain Sunit Krishna, a test pilot of the LCA Tejas Mk1, spoke to NDTV India and said, "With time, the technology has to be improved and have to be integrated. The Indian Air Force wanted new systems to be integrated into the Tejas so that it could be in service for the next three decades."

"The aircraft might look similar from the outside, but new electronics, processors, display systems, and the hardware of fly-by-wire systems have been integrated...To list out, it has new AESA (Active Electronically Scanned Array) radar, air-to-ground, air-to-air modes and self-protection jammers, and the mission computer in MK1A is new and indigenous. The aircraft is future-ready," Group Captain Krishna said.

The design of an aircraft poses limitations to integrating new systems. The HAL has incorporated the latest technology with slight modifications in the design to give a newer aircraft.

The new variant will have almost 50 per cent more indigenous content than its predecessor. The MK1A version will have 40 more improvements than the previous one. The Tejas Mk1A will have the advanced Israel EL/M-2025 AESA Radar. It will soon be replaced by the Uttam AESA Radar, indigenously developed by Bharat Electronics Limited and the HAL.

The Uttam Radar can track multiple targets and reportedly has a range of more than 200 km to give the aircraft a 360-degree scanned view of its surroundings. It will be used in the later variants like Tejas Mk2 and the Twin Engine Deck-Based Fighters (TEDBF).

The HAL has maintained a commonality between the Mk1 and Mk1A variants. The new version will have enhanced situational awareness with a slightly bigger canopy and changes in the jet aerodynamics to improve its manoeuvrability.

Mk1A will have around nine hard points on its underbelly to carry various types of weaponry like the Beyond Visual Range (BVR) missiles, Air-to-Air/Ground missiles, and Advanced Short Range Air-to-Air missiles (ASRAAM). External self-protection jammer pods will allow the aircraft to engage in electronic warfare.

An indigenously developed digital fly-by-wire flight control computer was integrated into the Tejas jet. Fly-by-wire systems in aircraft replace mechanical flight controls with an electronic interface

"In a significant development towards Tejas Mk1A programme, the digital fly-by-wire flight control computer (DFCC) was integrated into prototype LSP7 and successfully flown on February 19," the defence ministry said.

"The Tejas Mk1A will have an advanced electronic RADAR, warfare and communication systems, additional combat capability and improved maintenance features," HAL said.

The new Electronic Warfare Suite consists of a Radar Warning Receiver (RWR) system & Advanced Self Protection Jammer (ASPJ) pod will be installed into MK1A. The purpose of the system is to protect the aircraft against ground-based acquisition radars, fire control radars, anti-aircraft artillery and airborne multimode radars.

Tejas - Lightest, Smallest

Tejas is the smallest and lightest aircraft in its class and the dimensions and the extensive use of composite structure make it lighter. The 4.5 generation aircraft can be used for multiple roles like ground attack, interception, air-to-air combat and air defence.

The air force plans to raise the first squadron of the indigenous LCA Mark 1A fighter aircraft squadron at the Nal air base in the Bikaner district of Rajasthan near the Pakistan front. The Tejas will replace one of the two MiG-21 squadrons already stationed, ANI reported.

The Tejas Mk1, Mk1A, and Mk2 variants will replace the MiG-21, MiG-29, and SEPECAT Jaguar of the Indian Air Force in the future.

In 23 years of its history since the first test flight in 2001, the Tejas aircraft has maintained an excellent flight safety record. In March, a Tejas from the No.18 squadron crashed in Rajasthan, but it was the first such instance in 23 years of its history and almost eight years of operational deployment.

Nigeria, Philippines, Argentina and Egypt have shown interest in procuring indigenously-developed Tejas Light Combat Aircraft, CB Ananthakrishnan, the Chairman and Managing Director of Hindustan Aeronautics Ltd, earlier said.