IAF's Jaguars face retirement by 2024

The retirement of the Jaguar would create a six squadron gap in the IAF's combat fleet which would cost $20 billion-$30 billion to fill, reports Ajai Shukla.

The future of the Indian Air Force's six squadrons of Jaguar strike fighters is hanging in the balance.

The IAF has regarded the Jaguar as under-powered ever since it entered service in the late-1970s. Now, wear and tear on its twin Rolls-Royce Adour 804/811 engines has reduced the aircraft's thrust even further -- by an estimated 15-20 per cent.

As a result, the Jaguar faces difficulty in carrying out its demanding combat role: Flying low and fast, deep into enemy territory; bombing its ground target accurately in a single pass and then screaming back to base, ahead of enemy interceptors. In such missions, power is essential for survival.

"A new Adour 811 engine initially provides about 32.5 KiloNewtons (kN) of thrust. But after about a decade of service, it drops to barely 26 kN," says a senior IAF pilot with extensive experience flying the Jaguar.

Aiming to replace the Jaguar's underpowered engines, Hindustan Aeronautics Ltd and the IAF negotiated for a decade with US defence giant, Honeywell, to 'retro-fit' its F-125IN turbofan engines into the fighter.

That was expected to make the Jaguar operationally viable for another two decades since the F-125IN engine delivers an impressive 40.4 kN of thrust, with full afterburners.

However, negotiations with Honeywell have proved futile. The US company wants a price the IAF considers exorbitant and is unwilling to pay.

IAF and HAL sources say Honeywell has quoted a price of $2.4 billion for 180 new F-125IN engines -- which include 160 engines for 80 twin-engine Jaguars, plus 20 spare engines.

The cost of each engine thus works out to $13.3 million, or about Rs 95 crore (Rs 950 million).

The cost of 're-engining' each twin-engine Jaguar, therefore, adds up to a prohibitive Rs 210 crore (Rs 2.1 billion), including HAL's charge of Rs 20 crore (Rs 200 million) per aircraft for integrating, flight-testing and certifying the new F-125IN engines.

With the IAF buying the improved Tejas Mark 1A fighter from HAL at Rs 315 crore (Rs 31.5 billion) per aircraft, it regards Rs 210 crore too much to pay for a more powerful power plant.

With Honeywell negotiations broken down, HAL is back talking with Rolls-Royce, which built the Jaguar's original Adour Mark 804/811 engines.

In extensive discussions over the last four years, Rolls-Royce has proposed refurbishing the Jaguar's power plant by replacing worn out engine components with brand new replacements from the Adour 871 engines that HAL builds in Bengaluru for the Hawk trainer the IAF bought in 2004.

A technical white paper that Rolls-Royce authored at the request of the IAF said: 'It is proposed to introduce Mark 871 hardware, where appropriate, into the Mark 811 to help regain engine performance… Performance modelling predicts that an additional 13-18 per cent more thrust than the baseline Mark 811 is achievable at take-off on hot day conditions.'

Rolls-Royce assured the IAF: 'This prototype configuration has already been demonstrated on the sea level test bed at Rolls-Royce Bristol.'

The white paper is confident of overcoming technical difficulties. 'Some of the Adour Mark 871 hardware was originally designed to be interchangeable with Mark 811 components.'

'At a module level, many modules can be interchanged directly (noting that some components are common to all marks),' it said.

If Rolls-Royce's proposal does not materialise, the IAF's 110-odd Jaguar fighters will start retiring by 2024; with all of them likely to be phased out by 2030. This would seriously disrupt the IAF's force planning, creating a six-squadron gap in the IAF's combat fleet, which would cost $20 billion-$30 billion to fill.

Phasing out the Jaguar would also render fruitless the sophisticated avionics upgrades that HAL has carried out to its mission systems, making it a far more potent and accurate fighter-bomber than when it first came to India.

The upgrades include HAL's latest navigation-attack system called DARIN-3, which can guide the Jaguar unerringly to a target hundreds of kilometres away, even in the dead of night.

Meanwhile, there is growing scepticism, especially within HAL, about whether the F-125IN Honeywell engine can be integrated into the Jaguar.

"A fighter's airframe is engineered to match with an engine and the Jaguar's is matched with the Adour engine. One can keep tweaking the engine to get more efficiency out of it. But it is difficult to replace a fighter's original engine with another type," said an engineer who is familiar with this project.

In four years of exploratory talks between the IAF and Rolls-Royce, the cost of refurbishing the old Adour 804/811 engines with Adour 871 parts has not yet been discussed. However, HAL and the IAF officials both agree, 'refurbishing' the old Adour engine will be significantly cheaper than 'retro-fitting' the new Honeywell one.