India Seeks at Least 80% ToT of Russian 177S 5th-Gen Engines for Su-30MKI Upgrade under Super Sukhoi Program

India has laid down strict conditions for the potential acquisition of new Russian fifth-generation jet engines to upgrade its formidable Sukhoi Su-30MKI fleet.

According to official sources, the Indian Ministry of Defence (MoD) and the Indian Air Force (IAF) have communicated to Moscow that any agreement must involve a minimum of 80% Transfer of Technology (ToT), a significant increase over previous arrangements.

Furthermore, India is insisting that Russia conduct the final development testing of its proposed new engine within India.

Russia's state-owned United Engine Corporation (UEC) has presented two engine options for India's consideration.

The first is the AL-41F1S, which currently powers Russia's Su-35 fighter. The second, more advanced option is the "Product 177S," a next-generation engine incorporating technologies from the engine developed for Russia's Su-57 stealth fighter.

These powerplants are being proposed for the comprehensive "Super Sukhoi" upgrade program for India's fleet of over 240 Su-30MKI jets and potentially for India's own fifth-generation stealth fighter, the Advanced Medium Combat Aircraft (AMCA).

While the offer was first tabled during high-level meetings in 2024, the Product 177S engine garnered significant attention from IAF officials at the Aero India 2025 exhibition.

Its advanced specifications promise a substantial performance boost, including a thrust of 18–20 tons, a notable improvement over the 12.5 tons produced by the current AL-31F engine.

The new engine also offers greater fuel efficiency and design elements compatible with stealth technology, making it a key component for a true generational leap in the Su-30MKI's capabilities.

However, the IAF has shown less enthusiasm for the AL-41 engine. Defence sources indicate that this engine provides only "limited operational advantages" over the existing AL-31F. While more powerful, integrating the AL-41 would necessitate costly and extensive modifications to the Su-30MKI's airframe.

This is seen as an inefficient investment, particularly as the fleet is already undergoing a ₹20,000 crore enhancement with Indian-made avionics, the Uttam Active Electronically Scanned Array (AESA) radar, and BrahMos-A supersonic cruise missiles.

The interest in the developmental Product 177S is therefore much higher, but it comes with its own set of challenges. The engine is not yet mature and has not been cleared for serial production, making its performance and reliability unproven.

To address this, India has demanded that Russian engineers be deployed to complete the engine's validation and testing on Indian soil. This move is designed to mitigate developmental risks and ensure the technology is proven effective for Indian requirements before any large-scale commitment is made.

India's insistence on an 80% technology transfer is a cornerstone of its "Aatmanirbhar Bharat" policy in the defence sector.

This demand is informed by past experiences, such as the local manufacturing of the AL-31F engine by Hindustan Aeronautics Limited (HAL) at its Koraput facility, which operates with around 60% ToT. While this has reduced reliance on Moscow, India still needs to import critical components like engine turbine blades.

Achieving a higher level of ToT for the Product 177S would allow HAL to master cutting-edge engine technologies vital for the AMCA program and future indigenous aircraft projects.

The outcome of these negotiations may be influenced by the current geopolitical landscape. With its relations strained with Western nations, Russia may be more willing to agree to India's stringent technology-sharing demands to secure a major defence contract.

Simultaneously, India's growing defence partnership with the United States, highlighted by the recent agreement to co-produce GE F414 engines in India, gives New Delhi significant leverage.

The final decision now rests on Russia's willingness to meet India's firm conditions for what could be one of the world's largest fighter upgrade programs.

 

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[bks78]

177S engine is not committed to be fitted with any Russian fighter jet in which case UEC is better to opt for TOT with India to be fitted with SU30 MKI.

 

[sanket]

Su-30 upgrade. I was long saying there should be an engine upgrade too. I was the alone who was saying the IAF should consider the AL-51 derivative with the Su-57 offer. Good stand by IAF as well as MoD with 80% ToT and in-country testing for an engine that would reduce dependency on Russia, and HAL would be able to absorb the engine tech. This 117S engine would be contemporary still in 2060. I have 1000 times said in the future, the Super Sukhoi can carry heavy weaponry including a Hypersonic Missile that will put Super Sukhoi minus an internal weapon bay, non-composite material airframe with the latest avionics/sensors.

 

[Anonymus]

We need an engine for SU-30MKI. If IAF is thinking to operate it till 2060, then 177S is a good option if IAF is interested.

Although sources of Raunak Kunde are highly unreliable, so the validity of this article and claims are highly questionable.

 

[P.K Senapati]

Product 117S engine from Russia at HAL with 80 percent ToT and indigenisation of all critical parts involving private companies will keep Su-30 flying for a long time. Any delay in AMCA will not affect defence preparation.

 

[Senapati]

We are not selecting Al41 but a much better 177S variant.It has better thrust fuel efficiency life and stealth nozzle features.
It has been told changing from present Al31 to 177S will not require any measure structure or mounting point modificatio as it matches in length diametre and mounting points.
There is some intelligence in going for engine upgradation for improving Su30 performance .We can not say that Super sukhoi is for replacing radar and missiles with indigenious units from India.

 

[Ankit]

Biggest mistake will be if TOT is handed over to GTRE. Take it as an opportunity and hand over TOT to any private entity. Private organisations' learning curve will be fast and they will absorb the technology faster as scientists and engineers will be highly talented as compared to failed organisations like HAL.

 

[Baiju Bhaskaran]

It is a good opportunity for IAF and HAL. We should go for all upgrades with 177S engines. I have always been in favour of additional 36 upgraded Sukhois with new engines.

 

[Sam]

Su-30 upgrade. I was long saying there should be an engine upgrade too. I was the alone who was saying the IAF should consider the AL-51 derivative with the Su-57 offer. Good stand by IAF as well as MoD with 80% ToT and in-country testing for an engine that would reduce dependency on Russia, and HAL would be able to absorb the engine tech. This 117S engine would be contemporary still in 2060. I have 1000 times said in the future, the Super Sukhoi can carry heavy weaponry including a Hypersonic Missile that will put Super Sukhoi minus an internal weapon bay, non-composite material airframe with the latest avionics/sensors.

I believe Izdeliye 30 and Izdeliye 177S both are different, and if reports are to be believed, Izdeliye 30, which is the AL-51F engine, is nearing its mass production by the end of the year. Whereas, 177S, which is a derivative of the AL-51F engine, will require some time for the engine to mature. I don't know whether the testing phase of Izdeliye 177S has started or not, but we should only consider the Su-57 deal if Russia can integrate the Izdeliye 30, which is the AL-51F engine, into the Su-57 deal to India because the AL-51F is more advanced with supercruise ability and enhanced stealth capabilities.

 

[Kira]

We need an engine for SU-30MKI. If IAF is thinking to operate it till 2060, then 177S is a good option if IAF is interested.

Although sources of Raunak Kunde are highly unreliable, so the validity of this article and claims are highly questionable.

True, the only thing that India now needs from Russia is this engine and not the unproven Su-57.

 

[SURESH RAO]

Go for it. Immediately get a few 117S engines from Russia in flyaway condition. Test these engines on a few Su-30MKIs and get them certified for the Su-30MKI ASAP. Don't waste time.

 

[abhinav srivastava]

Since the current engine is giving good power output and future GaN radar will consume less power, why do they need a new engine? Carry on the upgrade of radar and electronics faster.

 

[Shiva Shankar]

Since the current engine is giving good power output and future GaN radar will consume less power, why do they need a new engine? Carry on the upgrade of radar and electronics faster.

New engine is far ahead in its technology and performance. At the same time, even the existing engine, although India is able to make it, is only using a kit provided by Russia, so it was not 100% ToT.

India faced issues because of the previous AL31 deal of not having 100% ToT. So, the current deal, it wants, is not to repeat the mistake. Russia agreed to 100% ToT and shared details, but Indian scientists were not good enough to be able to reproduce them perfectly.

So, the existing setup was not cleared in tests for mass production. This is where we are stuck, and we need Russian scientists to take up the responsibility to complete it. Maybe, officially 100% ToT has happened, but unofficially something is missing. These things happen in highest-end technology-related fields. They will smooth out, especially between India and Russia. It is just a matter of time. No need to look at it with magnifying glasses.

 

[Vf Feb]

Let's think logically... Today or tomorrow, India will order a minimum of 2-3 squadrons of Su-57s for sure. As Rafale is ordered (36+26 = 62), let's assume 50-60 Su-57 planes in three squadrons. We will need twin-engine Su-57s (120+120 = 240 Su-57 engines) in their lifetime with replacements, so it makes sense to get 6000 hours MTBF new 5th-gen engine Izdeliye 30 or 117S with ToT in India. The same will also be used in less throughput mode in Su-30MKI, so it makes it 350-400-500 new 5th-gen engines from Russia. Safran & RR's offer for AMCA is separate for 130kN. We need both as India cannot rely on European countries alone, nor can we rely on Russia alone. The US is now out of the picture for advanced engines. GE F404 and GE F414 are definitely in the US basket to fulfill or not to give.

 

[vasu gali]

India should demand 117S for SU30MKI and AL-51 with SU57 with TOT, otherwise no deal because of the US CAATSA threat. Otherwise, India may lose GE 404/414 engines and also become a slave of Russia, which then will be exploited by both Russia and China, forcing India to look to useful but costly France and Israel, who may be pulled back by the US.

 

[Sandeep]

The article does make a good point on why we should just stick to the AL31 engine as we have already built the engine manufacturing infrastructure, a MRO facility and have a well trained, educated and skilled workforce with experience who can with no issues.

Even if they gave 80% of the technology of the AL31, AL41 or 177S engine we would still need to find out the cost of producing one engine, what technology will we receive, what local manufacturing is allowed, what and where would the raw materials come from etc. It’s highly unlikely that they will give us 80% of it unless we buy it for billions.