Rendering of India’s Twin Engine Deck Based Fighter (TEDBF) concept with Key features

Future twin engine variant of Tejas aircraft will feature folding wings for aircraft carrier deployment. The new fighter-jet will be designed to operate from the deck of India's two aircraft carriers INS Vikramaditya and the soon to be inducted INS Vikrant

New Delhi: In twelve years from now, a twin engine variant of India's TEJAS fighter could start replacing Russian built MiG-29K jets deployed on board the Indian Navy's aircraft carriers INS Vikramaditya and Vikrant which is yet to be inducted.

Detailed concept drawings of the fighter, dubbed the Twin Engine Deck Based Fighter (TEDBF), are being studied by the Aeronautical Design Agency (ADA) and Hindustan Aeronautics Limited (HAL) which would eventually build the fighters if their development is funded by the government. What's more, the design of an Air Force variant of the jet, the Omni Role Combat Aircraft (ORCA), with significant design differences, is also being studied. This variant would weigh a ton less than the Naval variant since it would not need heavy reinforced landing gear required for operations from the deck of an aircraft carrier reported a news media website.

The Aeronautical Development Agency (ADA) controlled by the Defence Research & Development Organisation (DRDO) will develop a Twin Engine Deck Based Fighter (TEDBF) for the Indian Navy (IN) instead of persisting with the development of a Mk2 variant of the LCA-Navy (NLCA) design. The DRDO offered to develop a new twin-engine deck-based fighter aircraft for the Navy based on the experience of the Naval Light Combat Aircraft (NLCA) and it should be ready by 2026, Navy Chief Admiral Karambir Singh said on 03 December 2019. He also noted that the Navy expected to have the first Indigenous Aircraft Carrier (IAC-1) Vikrant operational by 2022. “The Qualitative Requirements [QR] are being made. They said they should be able to push it out by 2026. If it meets our time and QR requirements, we will definitely take it [fighter aircraft],” he said at the customary annual press conference ahead of the Navy Day.

According to globalsecurity.org website, the advantages of a twin-engine design are many, first, it will have increased speed and manoeuvrability, the jet will have enhanced range because it can carry more fuel and with refuelling, it can be extended to well over 2000 km. It can carry larger combat loads. It is also less susceptible to mechanical failures or combat damage. It can carry larger combat loads. At high altitudes, using two engines will have tremendous supplemental benefits, as losing a single engine jet over water or land is a much more life-threatening experience. System redundancy is a tertiary benefit of multi-engine aircraft, since losing engine results in only a 50% loss in total available thrust, plus redundant generators and hydraulic pumps will allow the aircraft to fly. In addition, having two engines will reduce training losses.

Navy refused to come aboard the TEJAS-Mk2 program due to concern regarding its single-engine configuration. The program will run concurrently with ADA’s other programs such as the Medium Weight Fighter (MWF) [formerly the TEJAS Mk-II] and the Advanced Medium Combat Aircraft (AMCA) projects and utilise developments from them. TEDBF will be lighter than the proposed 25 tonnes Naval-AMCA, production of which will commence only after 2030 but will more capable than the troublesome MiG-29K operated by the Indian Navy on board INS Vikramaditya.

The Indian Navy informed that with the landing of the naval LCA on the Vikramaditya in January 2020, indigenous technologies for deck-based operations have been proven, which will pave the way to develop a new "twin-engine" deck-based fighter. With this feat, the indigenously developed niche technologies specific to deck based fighter operations have been proven, which will now pave the way to develop and manufacture the Twin Engine Deck Based Fighter (TEDBF) for the Indian Navy.

Detailed concept drawings of the fighter, dubbed the Twin Engine Deck Based Fighter (TEDBF), are being studied by the Aeronautical Design Agency (ADA) and HAL which would eventually build the fighters if their development is funded by the government. The design of an Air Force variant of the jet, the Omni Role Combat Aircraft (ORCA), with significant design differences, is also being studied. This variant would weigh a ton less than the Naval variant since it would not need heavy reinforced landing gear required for operations from the deck of an aircraft carrier.

The total design and development costs for prototypes of the aircraft ''would cost less than the Rs.12,780 crore India Specific Enhancement package'' signed between India and France towards customising 36 Rafale fighters being inducted into the Indian Air Force. The total design and development costs for twin engine variants of the TEJAS fighter would cost less than Rs.13,000 crores with each fighter for the Navy costing in the range of Rs. 538 crores. The Indian Air Force variant of the fighter would cost between Rs 35 crore and Rs.71 crores less than the Navy variant. The development time-scale for the project has been pegged at six years from the time initial funding has been provided.

Project designers say they could ''very comfortably develop'' the new twin engine TEJAS variant based on the experience they have gained in testing the Naval prototype of the TEJAS fighter. This prototype is expected to land on the deck of India's aircraft carrier, INS Vikramaditya, for the first time within the next few weeks. The prototype is powered by a single US-built General Electric F404-GE-IN20 turbofan engine which is not seen to be powerful enough to justify serial manufacture of a Naval TEJAS in its present avatar other than in very limited numbers.

The significantly larger twin engine TEJAS now being proposed would be fitted with two more powerful General Electric F414 engines and would have a significantly higher weapons payload and range. The additional thrust provided by two engines would also guarantee a larger safety margin for pilots while taking off and landing in hot and humid tropical weather conditions out at sea in the Arabian Sea and Bay of Bengal.

Weighing 23 tonnes, the Navy Twin Engine Deck Based fighter would be nearly twice as heavy as the 13.5 ton TEJAS Mk-1 fighter which had entered squadron service with the Indian Air Force, and rather more than the 17.5 ton TEJAS Mk-2 which was to be inducted into the Indian Air Force from 2030. The fighter would be in the size of the MiG-29K currently being operated by the Indian Navy on its aircraft carrier, the INS Vikramaditya and would have the ability of carrying a weapons payload of nine tonnes. It would feature folding wings to save space on the deck of aircraft carriers. The jet would likely have a top speed in the range of Mach 1.6, nearly 2,000 kilometres per hour.

Primarily designed for the Indian Navy, the fighter will feature folding wing configuration which helps the aircraft to occupy less space in a confined hangar of the aircraft carrier thus also reducing the footprint of the aircraft when parked on the flight deck or inside the hangar. A folding wing has some disadvantages compared to a fixed-wing. It is heavier and has more complex due to connections for electrical, fuel, aerodynamic and structural systems. In Renders, we can see both ORCA in the fixed-wing configuration for Air force and folding wing configuration for the Navy. The Naval TEDBF will be 1 tonne heavier at 24 tonnes when compared to Air force ORCA which will around 23 tonnes due to the heavier undercarriage and strengthen and raised landing gears which add 700-800 kg and another 200 kg for folding wing system and its additional hinges. Both the Navy Twin Engine Deck Based fighter and the Air Force Omni Role Fighter would host indigenous sensors and avionics which by the year 2020 were at an advanced stage of development. This includes an Active Electronically Scanned Radar (AESA) which can simultaneously track targets in the air and out at sea or over land with great precision. All the fighters would be built with "made in India" data links and communication systems to enable the jets in a formation to securely exchange critical sensor information during a mission. A host of made-in-India weapons including long range variant of the Astra air to air missile which had completed tests would arm the jets.

None of the future variants of the TEJAS being studied are a part of the Navy or Air Force's present procurement plans. ''More than 750 aircraft will need replacement between 2030 and 2050.'' By 2040, several older aircraft in service with the Indian Air Force, including the Sukhoi Su-30MKI, presently the cutting edge, would need to retire. Development of a larger, twin engine variant of the TEJAS, designers feel, is an incremental step forward as they simultaneously proceed with the design and development of a made-in-India stealth fighter called the Advanced Medium Combat Aircraft (AMCA), both larger, more capable and more expensive than variants of the TEJAS. The AMCA is expected to start entering squadron service with the IAF from 2040 if funding is secured. A twin engine variant of the TEJAS would be in the class of the Rafale, nimble with excellent sensor fusion. The fact that this would be entirely designed and developed in India would be a huge boost for ambitions in being an aerospace power.

A project designer pointed out that, ''A twin engine variant of the TEJAS would be in the class of the Rafale, extremely nimble with excellent sensor fusion,'' say designers working on the plans for the futuristic fighter. ''The jet would be extremely nimble with excellent sensor fusion. The fact that this would be entirely designed and developed in India would be a huge boost for our ambitions in being an aerospace power.'' 

The total design and development costs for prototypes of the aircraft ''would cost less than the Rs.12,780 crore India Specific Enhancement package'' signed between India and France towards customising 36 Rafale fighters being inducted into the Indian Air Force. ''The total design and development costs for twin engine variants of the TEJAS fighter would cost less than Rs.13,000 crores with each fighter for the Navy costing in the range of Rs. 538 crores.'' The Indian Air Force variant of the fighter would cost between Rs 35 crore and Rs.71 crores less than the Navy variant. The development time-scale for the project has been pegged at six years from the time initial funding has been provided. (Combining related series by globalsecurity, NDTV, TheHindu, ADA & DRDO)