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.