Kaveri & Aero-Engine: News & Discussion

[Rakesh]

Safran unveils higher-thrust M88 engine for Dassault Rafale F5 under T-Rex program
https://www.flightglobal.com/defence/sa ... 15.article
17 June 2025

Safran has unveiled the M88 T-Rex, an evolution of the in-service M88 engine, designed to power the F5 standard of the Dassault Aviation Rafale fighter. Available thrust with afterburner will increase by around 20% to 19,840lb (88kN) over the current version’s 16,500lb, says the French engine specialist. To achieve the higher output, Safran plans to introduce “significant, targeted upgrades” including an improved low-pressure compressor, new materials and better cooling in the high-pressure turbine, and a nozzle with optimised aerodynamics. However, the changes will mean the M88 T-Rex is no larger than the baseline variant and has the same fuel efficiency and cost of ownership.

During recent risk-reduction activity, Safran demonstrated the updated performance without increasing fuel consumption. Modules will be compatible between the two versions, simplifying fleet management and maintainability. “We’re proud to be launching this project, which will push the boundaries of the M88’s performance to meet the evolving needs of our armed forces customers in an increasingly unstable geopolitical context,” says Christophe Bruneau, executive vice-president, military engines, Safran Aircraft Engines.

“Development of the M88 T-Rex will also enable us to expand our technology portfolio, benefiting our entire product range and strengthening national sovereignty.” Safran is currently conducting additional risk reduction studies ahead of the engine’s development. A production decision is expected later this year. Qualification of the M88 T-Rex is aligned with the planned entry into service of the Rafale F5 standard in in the early 2030s.

[Rakesh]

Safran unveils higher-thrust version of M88 for future Rafale upgrades
https://www.safran-group.com/pressroom/ ... 2025-06-17
17 June 2025

At the Paris Air Show, Safran is unveiling the M88 T-REX, an evolution of its M88 engine. Compatible with future standards of the Dassault Aviation Rafale, this engine will build on the proven reliability and performance of the M88, while taking it to new limits with a thrust increase to 9 metric tons with afterburner. To achieve this level of performance, the M88 T-REX will incorporate significant, targeted upgrades. The improved low-pressure compressor will allow greater airflow intake. The high-pressure turbine will incorporate new materials and next-generation cooling circuits and the nozzle will benefit from optimized aerodynamics. With these enhancements, the M88 T-REX will retain the key advantages of the current M88 in terms of size, modularity, fuel efficiency and cost of ownership, while delivering 20% more thrust.

Maintainability and fleet management will also be simplified thanks to compatibility between the modules of the M88 T-REX and those of the current M88. “We’re proud to be launching this engine project, which will push the boundaries of the M88’s performance to meet the evolving needs of our armed forces customers in an increasingly unstable geopolitical context,” said Christophe Bruneau, EVP Military Engines, Safran Aircraft Engines. “Development of the M88 T-REX will also enable us to expand our technology portfolio, benefiting our entire product range and strengthening national sovereignty.” Safran is currently conducting risk reduction studies ahead of the engine’s development. Qualification of the M88 T-REX is aligned with the planned entry into service of the Rafale F5 standard.

[Rakesh]

VIDEO: https://x.com/AjayshreeSamby3/status/19 ... 6510553495 ---> Safran M-88 T-REX with enhanced 9 tons of thrust.

[Rakesh]

https://x.com/vguillermard/status/1934895909516583237 ---> @SAFRAN is launching an evolution of the #M88 engine, called the M88 T-REX. Compatible with the future (F5) standards of the Rafale of @Dassault_OnAir, its thrust will be increased by 20% to 9 tonnes with post-combustion.

[Cybaru]

Nice!

That means it may be possible to replace the GE404 with this engine in the future if something goes wrong.

Let's get a deal now that gets Kaveri to 404/414 and work on a new Kaveri120KN standard. That is the news we are all waiting for now...

I wonder if IN goes for this for increased thrust during takeoff allowing larger loads.

[Cybaru]

The other reason for TEDBF was as we wanted something with longer station time (more fuel) and higher thrust. If the higher thrust engines M88REX allow CFTs (which was showcased again during this Paris air show) to be part of normal ops, then the reason for TEDBF decreases IMO. TEDBF still does not have sanction and thats a different problem.

IMO, we should still get NLCA or TEDBF program out the door and order enough to make progress.

[basant]

If we are serious at all, design Mirage 4K like dual-engine, Kaveri powered LCA. It will be faster and force IAF to purchase it. Left to itself, IAF will keep sabotaging the indigenous programs with spurious SQRs, delays and khayali pulao engines that, if exist at all, are prone to sanctions or supply issues. This is the sane way every country (or group of countries like EU) with an engine & airframe tech works.

[Cybaru]

I don't understand why something like 404/M88REX can't be used for initial prototypes and even for operations for AMCA. Don't even need 414 for AMCA if there are delays there.

SupreCruise and all can come in due time. Get the prototype flying and sort out the million other issues. Don't stall the program for one metric.

[pravula]

I don't understand why something like 404/M88REX can't be used for initial prototypes and even for operations for AMCA. Don't even need 414 for AMCA if there are delays there.

SupreCruise and all can come in due time. Get the prototype flying and sort out the million other issues. Don't stall the program for one metric.

New engines are not a joke anymore with fadec, but it has been done on a regular basis (Su-57, JF-17, J-11, J-10, Jaguar come to mind)

[drnayar]

Safran unveils higher-thrust M88 engine for Dassault Rafale F5 under T-Rex program
https://www.flightglobal.com/defence/sa ... 15.article
17 June 2025

Safran has unveiled the M88 T-Rex, an evolution of the in-service M88 engine, designed to power the F5 standard of the Dassault Aviation Rafale fighter. Available thrust with afterburner will increase by around 20% to 19,840lb (88kN) over the current version’s 16,500lb, says the French engine specialist. To achieve the higher output, Safran plans to introduce “significant, targeted upgrades” including an improved low-pressure compressor, new materials and better cooling in the high-pressure turbine, and a nozzle with optimised aerodynamics. However, the changes will mean the M88 T-Rex is no larger than the baseline variant and has the same fuel efficiency and cost of ownership.

would it enable the Rafale to supercruise without afterburner ?

[Rakesh]

Safran and HAL strengthen their cooperation to produce LEAP engines forged parts
https://www.safran-group.com/pressroom/ ... 2025-06-19
19 June 2025, Le Bourget (France)

At the 55th edition of the Paris Air Show, Safran Aircraft Engines, the world's leading French engine manufacturer in the design, development and production of aircraft engines, signed an agreement with Hindustan Aeronautics Limited (HAL), India's leading aerospace and defense company, for the industrialization and production of rotating parts for LEAP engines. This agreement supports the government’s “Make in India” policy and follows the memorandum of understanding signed by Safran Aircraft Engines and HAL in October 2023 to develop industrial cooperation in LEAP engine parts manufacturing, as well as the contract signed last February by both partners to produce forged parts. Safran Aircraft Engines is thus continuing to expand its footprint in India and is extending the scope of its cooperation with HAL through the production of Inconel parts.

The objective is to support the strong growth of the Indian aerospace market and ensure the ramp-up of LEAP engines powering single-aisle civil aircraft. To this end, Safran Aircraft Engines is developing a complete aerospace ecosystem based on the creation of new facilities in India and closer cooperation with its major Indian partners such as HAL. “We are really proud to expand this long-standing partnership with Safran and to develop our industrial expertise in forging processes for Inconel parts for the LEAP program”, said Dr. D K Sunil, Chairman and Managing Director of HAL. “We are pleased to extend our collaboration with HAL, a key player of the Indian aerospace industry,” said Dominique Dupuy, Safran Aircraft Engines' Purchasing VP. “This industrial cooperation is part of our roadmap to diversify our production sourcing and strengthen our industrial footprint in India, so as to support the growth of domestic air traffic with our LEAP engine and prepare for future requirements of the M88 engine powering the Rafale.”

Safran Aircraft Engines is thus boosting its capabilities and presence in India, where it already operates five production sites in Hyderabad, Bengaluru, and Goa. A sixth site dedicated to maintenance, repair, and overhaul (MRO) of LEAP engines will open in Hyderabad by the end of the year. In 2022, Safran and HAL also set up the Safran HAL Aircraft Engines joint venture in Bengaluru, specializing in manufacturing components for the LEAP engine as well as the M88 engine. India is CFM's third largest market in terms of the number of engines in service, with 75% of the Indian commercial fleet equipped with CFM engines. Today, of the 500 aircraft operated by 7 Indian airlines with CFM engines, over 370 are LEAP-powered, and over 2,000 engines on order are for Indian airlines. In addition, Safran Aircraft Engines plans to develop its military collaboration with India on the M88 engine.

[williams]

Safran unveils higher-thrust M88 engine for Dassault Rafale F5 under T-Rex program
https://www.flightglobal.com/defence/sa ... 15.article
17 June 2025

Safran has unveiled the M88 T-Rex, an evolution of the in-service M88 engine, designed to power the F5 standard of the Dassault Aviation Rafale fighter. Available thrust with afterburner will increase by around 20% to 19,840lb (88kN) over the current version’s 16,500lb, says the French engine specialist. To achieve the higher output, Safran plans to introduce “significant, targeted upgrades” including an improved low-pressure compressor, new materials and better cooling in the high-pressure turbine, and a nozzle with optimised aerodynamics. However, the changes will mean the M88 T-Rex is no larger than the baseline variant and has the same fuel efficiency and cost of ownership.

would it enable the Rafale to supercruise without afterburner ?

Not at 88 kN. Basically they have made some incremental improvements. GE still holds advantage when it comes to CMC tech. Hence DRDOs first love of GE engines. However cooperation with Safran if it goes through will be better. They may part with more tech than GE. Safran's FADEC powers GE engines. However India need to demonstrate a bit more before any of these guys will signup for advanced collaboration.

[Rakesh]

Safran and HAL strengthen their cooperation to produce LEAP engines forged parts
https://www.safran-group.com/pressroom/ ... 2025-06-19
19 June 2025, Le Bourget (France)

In addition, Safran Aircraft Engines plans to develop its military collaboration with India on the M88 engine.

https://x.com/AjayshreeSamby3/status/19 ... 8220540234 ---> Safran Aircraft Engines announces construction of a new MRO shop dedicated to M88 engine in Hyderabad. It will have a capacity of 600 modules per year.

https://x.com/AjayshreeSamby3/status/19 ... 2216035740 --->

[maitya]

Safran unveils higher-thrust version of M88 for future Rafale upgrades
https://www.safran-group.com/pressroom/ ... 2025-06-17
17 June 2025

At the Paris Air Show, Safran is unveiling the M88 T-REX, an evolution of its M88 engine.
...
The improved low-pressure compressor will allow greater airflow intake. The high-pressure turbine will incorporate new materials and next-generation cooling circuits and the nozzle will benefit from optimized aerodynamics. With these enhancements, the M88 T-REX will retain the key advantages of the current M88 in terms of size, modularity, fuel efficiency and cost of ownership, while delivering 20% more thrust.
...

Writing after a while, so pls excuse the inevitable tardiness:

Highlighted the key aspects of this program ... again, and as usual, not a whiff on dry thrust increment levels, which is where all the real technological hurdles lie.
Only talking about 20% Wet Thrust improvements etc, which in itself (only wet thrust improvements) is of little practical value.
Betw do note, compared to other contemporary 4+ Gen TFs, current M88-2 does have some headroom wrt purely wet-thrust improvements (IMVHO to about 80KN levels).

Anyway, so there's no other way except, to assume that this 20% increment in Wet Thrust, also means 18-20% increment to the dry thrust levels as well (so essentially ~58-59KN dry thrust levels).
But that would mean ~6.5:1 dry TWR, which is pure 5th Gen levels.

Based on that assumption, let's try to analyse, what it really means wrt TF technology dev/implementation.

And at the very outset, this looks to be much more conservative than the F404 -> F414 "evolution" path, but still there are some similarities (in the approach) nevertheless.
The easiest/most-popular path for any dry thrust increment is to go the LP (i.e. Fan/LPC and LPT) route - as it doesn't require tinkering with the core.
Some of my earlier posts details out all these aspects.

But the singular most critical requirement for this approach to be successful. is to have higher (relatively) BPR - or, in lay-man terms, there needs to be enough bypassed mass available, so that it can then be further accelerated by the Fan/LPC to enhance the dry thrust.

And 0.3 BPR of the M88 does just that - corollary ofcourse is, trying the same with lower BPR TFs like Kaveri (0.16) wouldn't yield similar level of dry thrust boost (though some level of improvement, say around 7-8%, would accrue).

And that's most probably achieved via higher SPR design of the Fan/LPC stages, and maybe also via making them lighter (Blisk etc) - but to derive the full benefit of it, the LPT needs to be made more efficient, so that it can deliver higher rpm to the Fan/LPC system.
And which itself (LPT efficient improvements) can be achieved via either further LPT design improvements or making the LPT lighter or both.

Do note, in this context, a counter-intuitive point:
Just making the LPT lighter won't yield higher rpm of the Fan/LPC - yes it will exhibit improvement in the Transient regime but that will vanish in the Steady State regime.
Reasoning is simple phyzzziks onlee: Lower mass -> lower MI -> lower torque requirement.
To improve Fan/LPC rpm levels both LPT improvement (weight reduction etc) and Fan/LPC improvements (lower weight, higher PR design etc) are required, in conjunction.

Now this, reducing the LPT weight business, is where it gets tricky for M88 - as IIRC, it already uses intermetallic (Gammma-TiAl) turbine blades (that are decidedly lighter than the traditional Ni-Superalloy based ones). Now for further weight reduction, it can only come from CMC based Turbine blade, which then takes it to straight 5th Gen level of TF tech.

But I highly doubt, this LPT+LPC route improvements would alone deliver this claimed 20% dry thrust improvements - yes, maybe 2-13%, but that's about it really.
To get to 20% levels they will have to do some incremental improvements to the HPT complex (both blades and vanes) - which essentially means higher TeT levels.

Remember, one "drawback" of trying to improve the rpm of Fan/LPC stages is, most often than not, results in incremental higher mass inflow. Which in turn means higher SFC, if TeT is not suitably incrementally increased.

Now higher TeT for M88 is really interesting - it currently uses 1st Gen SC Ni-Superalloy (AM1) for HPT blades (and vanes) which achieves raw metal temp levels of approx. 1050deg C (side note: similar/same as DS CM247LC used in Kaveri).
And from this 1050deg C level, it is able to achieve 1575deg C (1850K) levels of TeT - a whopping 525 deg cooling architecture advantage. So, assuming 8YSZ TBC usage (so say a surface-temp limit of 1225deg C), it'd approximate to 350+ deg of film-cooling design (Laser/EDM drilling tech).

That's as cutting edge as it gets.

So further TeT increments would either require a brand new TBC architecture (pls refer to my prev series-posts on TBC for further details) or even more advanced film-cooling design.

Now if you are wondering, why I'm sidestepping next Gen SC superalloy usage aspects wrt this incremental TeT improvement argument. Well think carefully:
A next Gen, say 2nd Gen, SC superalloy usage would essentially mean higher raw-metal temp capability - say by another 25-30deg (for 2nd Gen SC). Now if the same 8YSZ TBC design is retained (meaning 1250deg C, the absolute ambient-temp limit), and having already attained that level via the current 1st Gen SC design, this addn raw metal temp capability wouldn't lead to any TeT increments as such.
Sure, the MTBO etc would definitely improve (refer the EDE program of F414) but not the TeT.

To fully utilise (purely via-a-vis higher TeT levels) the higher raw-metal temp capabilities of the higher Gen SCs, one needs to be currently achieving (via their current YSZ based TBC architecture) lower than 1250deg C levels of blade-surface temp levels. Otherwise, a different TBC architecture is must, one that allows for higher than 1250deg C ambient temp levels.

But I have, as usual, digressed again ... coming back to the discussion.

Trouble is, and I'm not sure, with the current Laser/EDM drilling tech available, if it is at all possible to further increment the film-cooling levels. Maybe a few 10s (say addn 20-25deg C) of deg is still possible, and that's what Safran et all have aimed for currently - and maybe that is enough for this program.
As the only other alternative approach would be via the firmly 5th Gen, and world-beater, Effusion-cooling tech employment - which I sincerely doubt, but then again, who knows, Safran et all may have achieved all that anyway.

Interesting times ahead ...

[williams]

As always very good Gyan Maitya sir. I now think (if we have extra money in the budget ..big if) it is worth the time to figure out the design and parallel DnD of TEDBF /ORCA using M88 engine. This is one way to de-risk GE single engine based Tejas Mk2 development.

[Rakesh]

https://x.com/Ray70409890/status/1937456087147675974 ---> All the 237 castings and 919 forgings of the AL-31FP turbofan have been indigenised and are made from raw material. 136 numbers of critical heavy forgings like turbine discs are imported due to absence of 20k ton forging press. All the 2,819 numbers of sheet metal, machine components, pipelines are made here.

https://x.com/Ray70409890/status/1937458368609943934 ---> Out of 129 non metallic components, 45 have been indigenised so far. 23 of the 58 LRU are now made here in India. 484 out of 815 spares needed for AL-31FP are made here by HAL and other MSME. 1385 lines of raw materials are required for maintenance of the AL-31FP turbofan. 399 lines have been indigenised.

[Cain Marko]

https://x.com/Ray70409890/status/1937456087147675974 ---> All the 237 castings and 919 forgings of the AL-31FP turbofan have been indigenised and are made from raw material. 136 numbers of critical heavy forgings like turbine discs are imported due to absence of 20k ton forging press. All the 2,819 numbers of sheet metal, machine components, pipelines are made here.

https://x.com/Ray70409890/status/1937458368609943934 ---> Out of 129 non metallic components, 45 have been indigenised so far. 23 of the 58 LRU are now made here in India. 484 out of 815 spares needed for AL-31FP are made here by HAL and other MSME. 1385 lines of raw materials are required for maintenance of the AL-31FP turbofan. 399 lines have been indigenised.

This is what the Tejas should've been designed around once they found out shortages in thrust...

[Ankit Desai]

UK or France? Cabinet waits for DRDO on combat aircraft engine

“Engines are a constraining factor… a strategic decision has to be taken. Both Rolls-Royce and Safran are contenders for fifth-generation Advanced Medium Combat Aircraft. A Cabinet note will be prepared from the DRDO side and circulated,”

-Ankit

[ritesh]

https://x.com/Ray70409890/status/1937456087147675974 ---> All the 237 castings and 919 forgings of the AL-31FP turbofan have been indigenised and are made from raw material. 136 numbers of critical heavy forgings like turbine discs are imported due to absence of 20k ton forging press. All the 2,819 numbers of sheet metal, machine components, pipelines are made here.

https://x.com/Ray70409890/status/1937458368609943934 ---> Out of 129 non metallic components, 45 have been indigenised so far. 23 of the 58 LRU are now made here in India. 484 out of 815 spares needed for AL-31FP are made here by HAL and other MSME. 1385 lines of raw materials are required for maintenance of the AL-31FP turbofan. 399 lines have been indigenised.

This is what the Tejas should've been designed around once they found out shortages in thrust...

But, isn't both belongs to different class?

[Aditya_V]

But, isn't both belongs to different class?

To make the point further a Mahindra Scorpio 2.2 Ltr Diesel will never fit in a Maruti 800 no matter what you do, we could try to get the M-53 , RD-33 Engines in Tejas - it will take a few years. All these take money and resources and Surplus orders which we are loathe to do. And this at a time when the import lobby was waiting for 1 crash to cancel the Tejas. At that time the Russians did not want to have an indigenous fighter and hence never helped in even integrating R-73 missiles on the fighter, the French were similar in attitude and saw us as long term cash cows. USA did not believe we can build something competitive outside their ecosystem unlike say Gripen, South Korea KF 21, which uses thier FBW, Radar, Weapons etc. Only when we were getting serious the US started delaying supplies. So I can understand the historical decisions. Russia is still not fully cooperating with Testing results for Kaveri Derivative engines. The French also seem less than enthusiastic and still behind the scenes pushing for MMRCA.

It like when it rains heavily it floods in Japan, China, USA, Germany, UK but we Indians should be ashamed for a few hours while the water drains absorbs in India.

Ideally we should be doing it over the last few years now that the GE is showing us the middle finger trying to see if M-53, RD 33 Fit- easier said than done and if we could get is flying in the LCA Tejas were reliable enough, Had low enough fuel consumption and low enough MTBF. Our experience with RD 33 engines in the late 80's/ 90s were terrible.

[SRajesh]

^^^Adityaji
There are 4 spokes in this Engine Wheel:
1.Politcos
2.Babus
3.Services
4.Import lobby
If two of the above four join together then no amount of jingoism is going to get us the engine tech.

[Aditya_V]

Yes, but lets get the History correct.

1. When LCA was conceived , it was just a wish list never to actually happen, a MIg 21 replacement with BVR, A2G roles and then Unbotium flat rating engine specs.
2. The USSR and India Procurement was never really interested, the wanted a continuous purchases from the Indians
3. In 1987, trying to Veen us away from the Soviet's the Ragen admin in 1987 supplies 11 of the then latest GE 404 engines doing duty in their F-18, when the IAF was struggling with the newly acquired Mig-29 with RD 33 Engine. It must have looked like a marvelous piece of tech back then.
4. In 2001 when the LCA TD 1 flies the knives are out for the program, people like Suresh Kalmadi want to shut it down
5. Our Kaveri engine gets stuck with Russian Test beds, neither the French, UK are ready to play ball.
6. Slowly our portotypes start flying and its time for orders in 2008, what do we do we order 20 IOC, 20 FOC in 2010 and want suddenly want Aircraft powered by F414. While all the way the MRCA circus is being played.
7. In fact had we struck a deal for MRCA jets, and Licensed manufacturing of M-53 derivative with a combined deal we could have circumvented this issue.
8. Now we are stuck with GE hoping uncle will allow us license Manufacturing.
9. But we are not acquiring Test beds to start developing our own series of engines which will at least give us local alternatives 10-15 years down the line.

As you said, Politcos, Babus, Services have to get together while keeping the import lobby at bay. I guess SWIFT engines, LEAP engines for A320's, Manik engines for Nirbhay, Engines for Lakhsya hopefully spur on a domestic ecosystem along with testing equipment so we have a engine few years down the line for AMCA.
One thing I know no TOT will ever happen in the true sense.

[SRajesh]

Funding for Kaveri has been on Drip Feed!
And another important factor in the continuous process of funding and support regardless of which party in power.
That Bipartisan support is lacking
Also the planners need to take hit as well as bulk of them have had a very narrow tunnel visions with no big picture view isn't it!!
And as you said the 'The Quest for the Unobatinium' from the services has not helped either

[Vayutuvan]

^^^Adityaji
There are 4 spokes in this Engine Wheel:
1.Politcos
2.Babus
3.Services
4.Import lobby
If two of the above four join together then no amount of jingoism is going to get us the engine tech.

Would No. 4 be able to payoff others? That might have been the case during non-BJP govt.

[Prem Kumar]

UK or France? Cabinet waits for DRDO on combat aircraft engine

“Engines are a constraining factor… a strategic decision has to be taken. Both Rolls-Royce and Safran are contenders for fifth-generation Advanced Medium Combat Aircraft. A Cabinet note will be prepared from the DRDO side and circulated,”

-Ankit

My read: deal will to to France (more trustworthy than the Brits). Rolls Royce offer will be used to negotiate with the French

Modi is an Program Manager par excellence. He can envision, launch, monitor & execute massive programs - has done so repeatedly. We need him to bring that same capability to some key defense projects, notably Homegrown Jet Engines. Others being AMCA, SSK/SSN. These are our breakout programs and we need him steering these, at least from a 20K feet level

Hope it happens

[Cain Marko]

This is what the Tejas should've been designed around once they found out shortages in thrust...

But, isn't both belongs to different class?

I could be wrong about this, but not if iirc.

Think about the Tejas mk2 and compare it to the iafs darling, mirage 2000. You'll notice that the two pretty much are the same class in terms of weight and dimensions. Now look at the m53 engine and compare it to the al31, again you'll notice that the dimensions are hardly different. Iows, a follow up LCA aka mk2 could very well have been built around the al31.

Even if it took a little longer and the bird turned out a wee bigger, in the long run (today) at least the engine would've been reliable!