Kaveri & Aero-Engine: News & Discussion

[drnayar]

So, to reduce foreign dependence, we are embarking on 2 multi-billion, decade-long projects with 2 foreign vendors

To reduce the risk of being dependent on one foreign supplier, India is embarking on projects with two foreign suppliers.

IMO, if there are resources available, then India should also embark on a third project with the Russians. But that may be stretching it too thin.

Why are you leaving out the Japs?

In the true spirit of Atmanirbhar and Sabke Saath, Sabka Vikas we need to help Japan to build up their aerospace industry

[uddu]

This collaboration with Brahmos should have occurred long ago. The program manager for Kaveri was sleeping. Sometimes the solutions are within and identifying them is their job. Anyways we are back to certification and testing the engine, how much more wasted time on this activity due to videshi test facilities. This should make the MOD babus sanction the appropriate test facilities including an aircraft with 4 engines. A GE Ohio like test facility for environment level testing is required. BTW bird hit testing is a requirement of certification and so are things like hail, storm dust, rain and so forth.

Regarding test facilities, the call should be taken by NaMo and Rajnath Singh. Here there is no third party involvement or objection to be raised. It's a test facility for DRDO. Should be given. I don't think any service chief will intrude himself and say, don't set up test facility.

[Rakesh]

A must read thread on X on the development (or the lack thereof!) of turbofans in India.

https://x.com/AnchitGupta9/status/20286 ... 15666?s=20 ---> I have been following the GTRE/ Kaveri Engine discussions intently. Before we go further, remember the Indian Air Force officer who started this journey: Air Vice Marshal Sailendra Nath Roy Chaudhury. Because he built the starting line. (1/25)

Twitter Thread on one page ---> https://twitter-thread.com/t/2028676383795515666

[S_Madhukar]

Sabka Saath Sabka Vishwas , time kharab to Sabki Laath

[Kanoji]

https://x.com/nitingokhale/status/2030095773329936897
@nitingokhale
Well said Sushant

https://x.com/sushantsareen/status/2029766075299287100
@sushantsareen
If only Indian twitterati and commentariat werent such snowflakes they would realise that China's rise was its own doing. It's rise was not an American gift. The Chinese planned well, worked well, their engineers didnt sell soap, coke or maggi or join the IAS or worse IRS. They innovated, they built, they invested, they educated their people. The Chinese miracle is of their own making. Similarly whether India will rise or not is in Indian hands. If India rises it wont be because the Americans or Europeans allowed us to or gifted it to us. And we will never rise as long as our first talking point with other countries is "transfer of tech". This is the height of imagination and profoundity of the Indian bureaucrat and techno-crat. Big powers will never allow anyone to equal them. That is a no brainer. If India has to rise, we will on our own genius or not at all. And we will have to find our own way to rise. We cant copy someone else. We must learn from others (assuming we understand we are not the repository of all wisdom in the world and get off our hobbyhorse of being vishvaguru) but we must find our own way to the top because every country has to find its own path.

Posting this here as this mindset is very much needed in the stakeholders responsible for the development of Kaveri and making India Atmanirbhar in jet engines.

[uddu]

A must read thread on X on the development (or the lack thereof!) of turbofans in India.

https://x.com/AnchitGupta9/status/20286 ... 15666?s=20 ---> I have been following the GTRE/ Kaveri Engine discussions intently. Before we go further, remember the Indian Air Force officer who started this journey: Air Vice Marshal Sailendra Nath Roy Chaudhury. Because he built the starting line. (1/25)

Twitter Thread on one page ---> https://twitter-thread.com/t/2028676383795515666

Sirji, who started is not issue here. Who completes it need to be discussed so that we can have an engine. We must be looking at who is taking responsibility for it today. If Rajnath singh and Shriman Modi is not doing their responsibility in ensuring HATF, then IAF chief can demand that the ministry approve the same. IAF Chief can make public statement to come in support of DRDO needs. He can simply state that we are looking at the HATF being approved by the government and hopefully soon, so that DRDO can speed up the Kaveri engine project not needing to Russia every time and take it to its conclusion.

[vera_k]

That thread is instructive. It looks like a clash of personalities, with a new administration abandoning old work on the GTX engine that was being incubated. Wonder if we're seeing a repeat of this now, with new engine programs being spun up, while the old one with Kaveri has not been completed.

[uddu]

it's understandable that the HLFT-42 is heavier with not using composites to keep the cost low. HAL should not be going for GE engines when it comes to HLFT-42. The reason being we again will have issues importing and relying on a foreign players. Since Kaveri cannot be used for the HLFT-42 needing more thrust for its weight and such, the best option is a derated variant of the 120KN engine in development. Otherwise, how much will be the profit margin in selling a desi fighter with a foreign engine and with limited availability etc, there is not much profit to be made and competition with foreign players become tough. Hope they choose the right Joint venture engine and ensure HLFT-42 is suitable for that. At any stage more power requirements are needed, the same 120KN engine can be used. Else the nation should be putting the money right now in the development of a desi Kaveri 2.0 that is similar in performance to F-414 based on the technology available with the current Kaveri

HAL Seeks 95-100kN Engine for HLFT-42 Trainer to Align with Tejas Mk2, Sidelining Kaveri for Primary Role
https://defence.in/threads/hal-seeks-95 ... ole.17111/
08 March 2026

By selecting an engine in the 100kN class, HAL is prioritizing operational commonality. This thrust range aligns perfectly with the General Electric F414-INS6 engine, which India has already cleared for local production through a major technology transfer agreement.

[Kailash]

Hlft42 ? Does HAL have the manpower to pull this off in time? This whole thing doesn't fit. Bae hawk that it is designed to replace is much smaller and far less capable than hlft42. This is a jf17 bandar equivalent of a mk2. Again feels like IAF wants a full fledged fighter but willing to pay only trainer prices.

It is not going with an indigenous engine - be it kaveri which is overweight and underpowered or a reverse engineered al31/ganga. So no strategic independence. Russian 177s or the Japanese xf9 or any clean slate design from RR only continued the import dependence, limited export options.

If it is based on a 120kn safran/gtre engine that'll get ready in 7-10 years time, it is already too late. Not to mention new airframe with new engine conundrum.

Only Kaveri/Ganga makes sense. May be this decision should be guided by good economic sense and historic track record of HAL. Really only two questions..

• How soon can they churn out the hlft42 , while maintaining mk1a/mk2 production rates?

• How cheap will it be to buy maintain and upgrade compared to mk2

[uddu]

DRDO Plans to Integrate Indigenous 5th-Gen Single-Crystal Metallurgy into Planned 120 kN AMCA Engine with Safran
https://defence.in/threads/drdo-plans-t ... ran.17132/
11-3-2026

(DMRL). Indian scientists initially developed a "directionally solidified" alloy known as DMD4.

While single-crystal blades are the gold standard, they are notoriously difficult and expensive to cast into complex shapes. DMD4 served as a sophisticated solution, offering high reliability and easier manufacturing for intricate engine geometries.

By iterating on this design and adding rare elements like ruthenium (Ru), researchers significantly improved the material's heat resistance and durability.

While France’s Safran brings world-class experience in core engine architecture, India's contribution of indigenous blade metallurgy ensures the partnership is a balanced collaboration.

This "division of labour" allows India to retain control over the "hot section" of the engine—the most critical and sensitive part of propulsion technology.

[Rakesh]

...

Saar, that Defence.in article is fake news. There is no HLFT-42 coming for the IAF.

IDRW.org and Defence.in are fake news websites designed to fool the public for the sole purpose of website clicks.

[Rakesh]

Sirji, who started is not issue here. Who completes it need to be discussed so that we can have an engine. We must be looking at who is taking responsibility for it today. If Rajnath singh and Shriman Modi is not doing their responsibility in ensuring HATF, then IAF chief can demand that the ministry approve the same. IAF Chief can make public statement to come in support of DRDO needs. He can simply state that we are looking at the HATF being approved by the government and hopefully soon, so that DRDO can speed up the Kaveri engine project not needing to Russia every time and take it to its conclusion.

Nobody is completing it uddu. There is no responsibility towards this.

IAF Chief and Air HQ is focused on completing the MRFA deal. Engine development is the last thing on their minds. All the speeches of Atmanirbharata is meant solely for public consumption. The demonstrated actions are opposite to the speeches.

[Rakesh]

https://x.com/Tej_Intel/status/2031630769161212092?s=20 ---> For students thinking of getting into aero-engine, join Gatishakti University for aero-engine MRO - supported by Safran.

Wiki Page ---> https://en.wikipedia.org/wiki/Gati_Shak ... avidyalaya

[ritesh]

News doing rounds on twitter, kaveri with modified afterburner put out 81kn. Can we hope it to power Tejas mk1a anytime soon?
https://x.com/HemanNamo/status/2025902791718269074?s=20

[Rakesh]

News doing rounds on twitter, kaveri with modified afterburner put out 81kn. Can we hope it to power Tejas mk1a anytime soon?
https://x.com/HemanNamo/status/2025902791718269074?s=20

We are inching there, slowly but surely. Very positive developments and staying hopeful.

As for powering Tejas Mk1A, most certainly...but will realistically happen at a future MLU (Mid Life Upgrade). While the engine has achieved 81kN of wet thrust, there is a lot more testing that needs to be done at a HATF and on a FTB, neither of which are with us now. Both of those will come in due course, but F404 is the only game in town at the moment.

The Tejas ecosystem has been built around the F404 and it will remain so, for the foreseeable future. IMVHO, the goal should be to exceed the 84kN wet thrust of the F404....as the wet thrust gets de-rated operating in India's varied climate. maitya-ji can articulate in greater detail on this topic and hopefully he will chime in...if he sees this post.

But exceeding the wet thrust of the F404 is crucial, as future upgrades (better radar, sensors and weapons) will require additional power than what the F404 currently produces. The short term goal is to start production of the KDE to mount onto the Ghatak UCAV. The long term goal (i.e. MLU) should be an after-burning variant of the Kaveri onto a "future" Tejas Mk1B.

[chaitanya]

Can some ghataks be modified to become drone-based flying test beds? If so, that would probably be the fastest and most cost-effective way to get an FTB at this rate

[bala]

While the engine has achieved 81kN of wet thrust
the goal should be to exceed the 84kN wet thrust of the F404

81 KN for tejas is more than sufficient. Most aircrafts don't need the high thrust regime, it is only used for fast escape but empties the fuel quickly. Aircrafts, like cars, cruise at around 1/2 power or less most of the times.

Getting Kaveri into Tejas should be the top priority for India. This implies getting over the test curve quickly and certification of the engine. Once it proves to be reliable then Tejas mid-life refit should switch to Kaveri.

Things like Ghatak etc are good as a test bed for the engine. The MoD babus should be hawk-eyed about the testing for Kaveri and smooth the path as deemed.

[vera_k]

Apologies for being a wet blanket, but this "news" does not compute without more information.

The engine was reported to be 135kg overweight in 2008.
Since then, a composite bypass duct was implemented, which should reduce weight by 20-25kg.
A new AFADEC was designed, which should reduce weight further.

And now this post says new materials were used.

All these improvements together should have brought the engine closer to weight of the F404IN.

What explains it being 130kg overweight then?

FWIW, another post from the same handle with a graphic saying 200kg weight reduction is needed

Roadmap

[dinesh_kimar]

Apologies for being a wet blanket, but this "news" does not compute without more information.
Roadmap

Yes , news indeed talks abt composite duct, etc. which saved weight.
However, new fan to reduce afterburner screech / distortion was reported.
New materials for hot sections , with resultant changes (DM4 blade?).
New afterburner from Brahmos Aerospace.
KADECU unit was upgraded
New beefed up starter unit -GTSU 110 MK-II
Localised AMAGB gearbox PTO shaft and localised bearings from HAL.

All these new stuff might have added their own weight penalties to the Kaveri engine. I believe such consequences are not unknown in Aero Engine development.

As a part of speculation from a layman, I would also venture to add that GTREs consultant SNECMA is not the same league as GE and Rolls Royce ( Largest engine is 95 KN M-53 on Mirage 2000, GE has 512 KN on GE-90, RR has 430 KN on Trent).

In component design, their fallback approach might be to increase Factor of Safety/ Material dimensions to deal with higher stresses ( various thermal and structural).

RR and GE might go along with new alloys, quintple laser holes, less Factor of safety for required life as specified by MTBO,etc.

All these changes might have their own weight penalty.

[Aditya_V]

Any idea why Kaveri, KDE are not being considered for HLFT 42 programme?

Shortage in THrust weight should matter lesser here given these are trainers, and meant to be cheaper and also to be considered for export where we would not need US approval

[Kanoji]

DRDO’s Kaveri Engine Complete Flight Trials in Russia!

[uddu]

Any idea why Kaveri, KDE are not being considered for HLFT 42 programme?

Shortage in THrust weight should matter lesser here given these are trainers, and meant to be cheaper and also to be considered for export where we would not need US approval

Weight. A composite variant of HLFT will be light weight and can use this engine. But want to use metal as much as possible to keep the cost down and import and pay high price for the engines. Our departments are more like count the peanuts and let go of the elephant.

[ashthor]

Any idea why Kaveri, KDE are not being considered for HLFT 42 programme?

Shortage in THrust weight should matter lesser here given these are trainers, and meant to be cheaper and also to be considered for export where we would not need US approval

How will they enjoy their US holidays then?

[Avinandan]

Any idea why Kaveri, KDE are not being considered for HLFT 42 programme?

Shortage in Thrust weight should matter lesser here given these are trainers, and meant to be cheaper and also to be considered for export where we would not need US approval

Weight. A composite variant of HLFT will be light weight and can use this engine. But want to use metal as much as possible to keep the cost down and import and pay high price for the engines. Our departments are more like count the peanuts and let go of the elephant.

I think HAL LIFT 42 was designed as a light LCA (performance of LCA Mk1 with up to about 1.6 Mach and 4.5-ton weapon payload) and not just an AJT (high subsonic) and for that they want a 90-100kN AB Thrust Class Engine is required.

LCA Trainer (Metal version) + Avionics upgrade for the so-called Mothership to + RD‑93/RD‑93MA+ Adding ballast weights (fore and aft wherever needed) to align with current could fit the job and cost and time to market albeit with minor compromise with the performance. In-spite of all that it would be competing with best of the LIFTs (e.g. Boeing-Saab Red Hawk LIFT).

Otherwise, IMHO If we really want to insist for a cheap reliable exportable HLFT 42 then we could as design a new aircraft with 2 engine version aiming with HTFE-25 with AB while using Jaguar Adour Engine for current testing.

We could as well buy Yak-130 with full ToT and MKI it

[uddu]

Meet the NJ100: The Atmanirbhar Jet Engine Haunting Pakistan's Sleep

[nash]

Very good news on engine development, looks like finally things are moving on this front.

https://alphadefense.in/index.php/2026/ ... e-testing/

What the NAETC Will Include

The National Aero Engine Test Complex is planned as a fully integrated, world-class testing hub within India. It will include:

A High Altitude Engine Test Facility to simulate real flight conditions at extreme altitudes
A Fan and Compressor Test Facility for evaluating compression stages
A Combustor Test Facility to assess combustion performance and durability
A Turbine Test Facility for testing turbine components under realistic stress conditions
An Afterburner Test Facility to validate thrust augmentation systems
Beyond supporting GTRE, this complex is expected to serve as a national resource for India’s wider aerospace ecosystem.

No update on FTB yet, but hopefully it will be logical next step.

[nash]

This is interesting update, I thought K 2.0 would be ~90KN :

http://x.com/DefenceDecode/status/2034949467204723056

Defence Decode®
@DefenceDecode
#DRDO's Gas Turbine Research Establishment is currently working towards certification of the GTX-35VS Kaveri in its 82 kN thrust class. Following certification of this baseline variant, discussions are underway to develop an upgraded Kaveri 2.0 with 85 kN+ thrust.: DR Ganesan, GTRE

[uddu]

This is interesting update, I thought K 2.0 would be ~90KN :

http://x.com/DefenceDecode/status/2034949467204723056

Defence Decode®
@DefenceDecode
#DRDO's Gas Turbine Research Establishment is currently working towards certification of the GTX-35VS Kaveri in its 82 kN thrust class. Following certification of this baseline variant, discussions are underway to develop an upgraded Kaveri 2.0 with 85 kN+ thrust.: DR Ganesan, GTRE

Probably Kaveri 2.0 is of same dimensions as current one. Plan seem to be to get the 82 KN variant manufactured and then when the 85KN thrust variant is available manufacture that and use that. Get step by step induction and usage on Tejas rather than waste years without any induction.

[Rakesh]

UPA-era oil payments are completed and now the big guns are coming out

https://x.com/Neetivaan/status/2034955609674850721?s=20 ---> Atmanirbhar Bhārat is the only way out.

[Rakesh]

Exclusive : India’s Big Step Toward Indigenous Aero Engine Testing
https://alphadefense.in/index.php/2026/ ... e-testing/
20 March 2026

[Rakesh]

VIDEO: https://x.com/cvkrishnan/status/2034985 ... 95884?s=20 ---> So as per Dr Ganesan of GTRE the last flight test of the full Kaveri engine was in 2010 more than 15 years back. All those rando defence handles that were recently claiming higher flight tested thrust for the Kaveri in recent times have some shame!

[bala]

What Dr. Ganesan said is about the Dry Engine, the core of Kaveri. Kaveri Afterburner bumps up the thrust to 80 kN range. This AB extra part is now tested and somewhat proven. Now the tricky part is to get the engine certified. This is where in-house testing facilities are required to simulate various environmental conditions including rain, snow, dust, heat wave, bird hit, etc and run the engine. You have to pass the hurdle to qualify putting engine onto piloted aircrafts like Tejas. The dry core will be flown on Ghatak autonomous flying vehicle.

India's R&D is lagging behind since the funding stream is crimped by the Babu IAS clan. Modi ji has to immediately 10x R&D budget in defence. This quantum leap in funds will make India Atmanirbhata in critical defence areas. DRDO, BARC, ISRO all of them require massive injection of R&D funds.

[uddu]

VIDEO: https://x.com/cvkrishnan/status/2034985 ... 95884?s=20 ---> So as per Dr Ganesan of GTRE the last flight test of the full Kaveri engine was in 2010 more than 15 years back. All those rando defence handles that were recently claiming higher flight tested thrust for the Kaveri in recent times have some shame!

Totally confused between KDE that has achieved higher dry thrust and Kaveri with afterburner.

[drnayar]

kaveri saga summarised ! Map reader in his dry humour


The true secret weapon lies in the testing infrastructure. Developing the core of a jet engine lacking a dedicated testing complex is exactly like trying to design a cutting edge semiconductor using a rusty abacus.

[vijayk]

So is this true or not???

https://x.com/HemanNamo/status/2035404110653231516

Kaveri Engine BREAKTHROUGH

Titanium Blisk → lighter core, higher efficiency
Afterburner tested → targeting 80–90 kN class
Indigenous test facility → ends foreign altitude trials

Supports Ghatak UCAV, Tejas upgrades, AMCA roadmap
This isn’t progress.
This is engine sovereignty.
#KaveriEngine #DRDO #MakeInIndia #AtmanirbharBharat

Grok analysis ...

Lightweight titanium blisk for efficiency gains: Fully confirmed. GTRE developed and demonstrated a titanium alloy blisk (blade-disk integrated component) that cuts weight by 20–30% per stage (by removing roots, hardware, and rims). This boosts fuel efficiency, pressure ratios, and performance. It was shown to Defence Minister Rajnath Singh during his GTRE visit and widely reported in early March 2026.

Successful afterburner tests targeting 80–90 kN thrust: True—the test happened. On 16 February 2026, Rajnath Singh personally witnessed a full afterburner run of the Kaveri (derivative) engine at GTRE. Reports confirm ~81–83 kN wet thrust was achieved in these trials. The 80–90 kN class is the aspirational target for an upgraded "Kaveri 2.0" variant (base dry Kaveri is currently ~49–52 kN); this was a major validation step toward it.
Indigenous high-altitude facilities: Recent major progress, but not fully operational yet. On ~20 March 2026, GTRE issued an RFI (Request for Information) for a National Aero Engine Test Complex (NAETC) that explicitly includes a High Altitude Engine Test Facility (HATF) to simulate real flight conditions (up to 15 km altitude, Mach 2+). The goal is to end dependence on Russian test beds (which have caused delays, e.g., a 3-year wait for slots). Possible sites: Challakere (Karnataka) or near Nagarjuna Sagar. This is a big step forward, but the facility is still in the planning/RFI response stage (not built or certified).
Applications for Ghatak UCAV, Tejas upgrades, and AMCA: Accurate on the roadmap. The dry (non-afterburning) Kaveri is the primary engine for the Ghatak stealth UCAV, with MoD targeting certification in 2026 for induction. Future higher-thrust variants (Kaveri 2.0) are discussed as stepping stones for Tejas Mk2 mid-life upgrades and AMCA, though these remain longer-term/aspirational (current fighters rely on GE F404/F414).

https://x.com/_TheTathya/status/2035702373172265045

India Targets 90–100 kN Kaveri 2.0 Engine as Indigenous Fighter Jet Power Breakthrough Nears

India’s jet engine program is entering a decisive phase as GTRE pushes toward certification of the Kaveri Derivative Engine (KDE) while simultaneously advancing Kaveri 2.0.

> KDE (~49 kN dry thrust) nearing flight certification
> Likely to power Ghatak UCAV & future unmanned platforms
> Next phase includes afterburning variant testing
> Planned integration on Tejas Mk1 as a flying testbed

Here's the Kaveri 2.0 Roadmap

> Target thrust: 90–100 kN (with afterburner)
> Built around a new core to overcome past limitations
> Intended for:
Tejas Mk2-class fighters
AMCA & next-gen platforms

Why this matters

> Reduces dependence on:
GE F404 / F414 (US)
Other foreign engine suppliers

> Gives India full control over:
Engine design & upgrades
Integration across platforms
Export flexibility

The strategy follows a clear phased path... certify the KDE, validate fighter integration, then scale up to the Kaveri 2.0 engine.

> Tejas Mk1 being used as a flying lab to fast-track real-world testing

If successful, Kaveri 2.0 will mark India’s entry into the elite club of nations with indigenous fighter jet engines.

[uddu]

We must be manufacturing the Kaveri variant that could provide 82KN thrust, which again will be good for the reason that the GE F04 is losing 10 percent thrust at higher altitude. While Kaveri can maintain it's thrust. 10 percent reduction means 84KN is coming to 76kn. So a Kaveri able to provide 82KN is also good. Then once the Kaveri 2.0 reach the needed 85+KN and further weight reduction, we can shift to using that. Else this import cycle will keep repeating with our engine not getting inducted.

[drnayar]

We must be manufacturing the Kaveri variant that could provide 82KN thrust, which again will be good for the reason that the GE F04 is losing 10 percent thrust at higher altitude. While Kaveri can maintain it's thrust. 10 percent reduction means 84KN is coming to 76kn. So a Kaveri able to provide 82KN is also good. Then once the Kaveri 2.0 reach the needed 85+KN and further weight reduction, we can shift to using that. Else this import cycle will keep repeating with our engine not getting inducted.

Quite right., making the engine is one., but serial manufacturing depends on components, suppliers et all.. it takes time to build up a whole ecosystem

[Rakesh]

https://x.com/firebase25/status/2035527 ... 27498?s=20 ---> Thread on Kaveri issues. IAF killed Kaveri successfully with their constant changing requirements, one of my colleagues who met with Mohan Rao clearly stated, "it was out of their control" angry they had been blamed for something that wasn't even their fault.

Twitter Thread on one page ---> https://twitter-thread.com/t/2035527228751327498

[Rakesh]

https://x.com/InsightGL/status/2035558825231864186?s=20 ---> Kaveri 2 Update

- GTRE has publicly pitched “Kaveri‑2.0” as a next‑gen engine (built around a new core) with a target of up to ~90 kN thrust.
- Aimed are Tejas Mk2 Class platforms & possibly follow‑on AMCA.
- India is already considering “National Mission Mode” for indigenous fighter engines fast‑tracking the development to ~5–7 years, but all depends on government funding.
- Safran has offered a consultancy‑plus‑investment package (~€1 billion scale commitment) to “make Kaveri flight‑worthy” & turn it into a production‑ready engine.
- Rolls‑Royce is also in talks with GTRE about broader collaboration on Kaveri 2.0, even joint‑development & technology transfer.
- If Kaveri‑2.0 succeeds, it offers a domestic alternative for Tejas MkII/AMCA‑class jets, reducing dependence on GE‑F404/F414 & French M88.
- But India also has to be ready to counter sabotage as there are many parties who would not like India owning an indigenous engine technology.

[bkswarti]

https://x.com/InsightGL/status/2035558825231864186?s=20 ---> Kaveri 2 Update

How reliable is this source. Hoping this is true.