Kaveri & Aero-Engine: News & Discussion

[sanman]

Will India Produce Jet Engines Next? What Do We Need To Build The Capacity?

[vera_k]

GE Aerospace Says Over a Dozen Suppliers at Fault for Shortages

15 different suppliers across supply chain to blame: CEO Culp
Says naysayers would be foolish to bet against China’s Comac

[maitya]

Interesting nugget on GTREs TV effort - from Alpha Defense:
TV effort by GTRE
Details about its Progress

[Dexter]

Will India Produce Jet Engines Next? What Do We Need To Build The Capacity?

Video says that GE has already given machines to create fine features so there is finally some useful ToT

[sanman]

Video says that GE has already given machines to create fine features so there is finally some useful ToT

We seem to be very hostage to the machines that build the machines

[Dexter]

Admiral saab

I want to send you a DM. Can you please allow or send me a Hi to which I can reply.

[Rakesh]

Admiral saab

I want to send you a DM. Can you please allow or send me a Hi to which I can reply.

Sent you email.

[sanman]

More Russian Engine Options for India

[isubodh]

More Russian Engine Options for India

We are looking for Jet engine ToT from France, US but why we never got it from Russia.
If Russia is not willing even after buying so many fighters, what chance we have with France or US.

[sanman]

We are looking for Jet engine ToT from France, US but why we never got it from Russia.
If Russia is not willing even after buying so many fighters, what chance we have with France or US.

I assume Russia is now upping their offer, because they see us looking increasingly toward GE after Trump's re-election.

[maitya]

We are looking for Jet engine ToT from France, US but why we never got it from Russia.
If Russia is not willing even after buying so many fighters, what chance we have with France or US.

I assume Russia is now upping their offer, because they see us looking increasingly toward GE after Trump's re-election.

Unfortunately, they are not ... they are still stuck with a notion that this turd-world nation is technologically not capable enough to handle 4-4.5 gen turbofan engine end-to-end manufacturing.
And can't blame them - without an engine like Kaveri in operational service, there's no way to demonstrate indigenous capability etc.

All the Russian engines that we Lic Mfg (aka screw-driver) in India like RD-33MK, AL-31FP etc, are barely 4th Gen at best - and are simply not in the league of true blue 4+ Gen F414 or M88 or EJ200 etc. And worse, even for them, Russia has made sure all key component raw material (and also their mfg technology) have to be imported from Russia.

Pls note, we do have indigenous technological capabilities that are about a gen more advanced than those employed for RD-33MK/AL-31FP etc - but without an operational engine in mass-manufacturing (and spanning over atleast a few years), where's the proof of those technological capabilities.
No wonder, Russians think that they can just offer AL-41F (just an upgraded AL-31F, and those upgrades are well within Indian's reach), for the Super Sukhoi program, and we'd simply lap it up.
etc etc.

The exception of course is Izdeliya-30 - from whatever little info that has been revealed, it's true-blue 5th Gen turbofan - maybe still not in league of F119/F135 etc (only very less has been revealed so far), but maybe not that far either.
And for almost a decade (FGFA days) we have been asking for these technologies or for atleast an Lic Mfg arrangement.
But nothing came thru, so far.

So wrt Russian TF engine tech help etc, is concerned - we are stuck between the following two:
1) The TF technologies (of RD-33MK or AL-31F), that can be made available, if we really press for them is not the technologies that we are really looking for (from TF D&D perspective).
In fact, had the threat of Warranty being voided etc, not been there, I'm pretty sure, a good upgrade for them (in line of F404 -> F414) could have been designed and implemented by us alone.

2) Russian has not agreed to share any of the 5th Gen tech of Izdeliya-30 ... not even for Lic Mfg.
So far atleast ... and I suspect, such technologies will be very tightly coupled with LiC Mfg deal of some 100+ Su-57 (or it's twin-seater FGFA derivative) - not happening!!



Between, I think you are mistaken, if you think GE (via GE-414 ToT) will have any value-add wrt our indigenous TF D&D is concerned ... you may want to refer to some my posts on this thread over last couple of years.

However, pls don't get me wrong - such ToAsT deals, would certainly help a mass-manufacturer (like HAL), to master (and also accumulate experience) various aspects of mass-manufacturing technologies of modern 4+ Gen TF engines - even though, some of the key systems (e.g. Turbine components) will be full imported (and then assembled and tested here).

Also pls note, this GE-F414 (4+ Gen) ToAsT based mass-manufacturing, is the evolutionary next step from first Adour (3rd Gen), then RD-33MK (4th Gen) and then onto AL-31FP (somewhat "incremental" 4th Gen) mass-manufacturing.
Ofcourse, it would have been ideal, if we were able to secure some level of "indigenous parts replacement" type agreement for the RD-33MK or AL-31FP, similar to what has been done for the Adours decade+ back.
pls refer to posts from 2009-2011 timeframes in this very thread archives
But nevertheless, it's still a net value-add wrt TF mass-manufacturing technology devt and TF MIC dev pov - after all, just Turbines or even the Hot Sections doesn't make the entire TF.

This expertise/experience will certainly come handy productionising whenever any of our 4+ Gen indigenous TF design is ready (read fully certified and mass-manufacturing ordered).

Sorry for digressing from your original post ...

[Haridas]

Dhanyawaad bandhu.

Bottom line is unless Bharat puts money on table (~$10 Bn) spread over 6 to 10 years for 5 or 5.5 gen engine development and use of that engine on Indian crafts in qty 2000 pcs ($10 bn) over another 10 years, to make it worthwhile.

The catch-up needed in many engineering deciplines, all around digital twin core of concurrent engineering.

[NRao]

Dhanyawaad bandhu.

Bottom line is unless Bharat puts money on table (~$10 Bn) spread over 6 to 10 years for 5 or 5.5 gen engine development and use of that engine on Indian crafts in qty 2000 pcs ($10 bn) over another 10 years, to make it worthwhile.

The catch-up needed in many engineering deciplines, all around digital twin core of concurrent engineering.

Tactical:

$0.5 billion per engine per year

Two engines

________________________________________________________________________-

Strategic:

Dedicated funding for at least 10 universities.

Family of engines - 50 kN to 200 kN

________________________________________________________________________

More than probable

[NRao]

engines

[maitya]

Upping the thread, with a few tidbits on Kaveri program updates:

Recently there were a few reports that the Brahmos Aerospace has completed development of the AB for the Kaveri Dry engine, and that it's producing 29KN of "additional" (read Wet) thrust - the context of this "news" can be found in this old post.
However, this video report by Alpha Defense sort-of debunks it, by way of stating that, nothing of that kind of status-reporting by Brahmos Aerospace or by GTRE hasn't happened yet - and maybe during the AeroIndia 25, true status will emerge.

That said, this report does bring out a few more following points, in addition to those already reported earlier (refer to my post above):

1) In addition to developing the AB, Brahmos Aerospace is also entrusted with integrating the Kaveri Dry Engine with this new AB.
In this context, do note there were reports a few months back, that Godrej has already delivered a few Kaveri dry engines.

2) A new Fan was developed recently, and this new Fan when integrated with the already developed dry Kaveri, is producing 51KN dry thrust.
Again in this context, recall that the dry Kaveri version that was taken to Gromov Test Center, for high Altitude testing, had achieved 48.5KN dry thrust (expectation was 46KN).
Also remember, dev of this new Fan was reported, albeit completely disjointly, about an year or so back (will have to dig out that ref).

[Kailash]

So this new fan is part of the 8 engines produced already. Will this additional fan fit within the envisaged dimensions/weight of the afterburning Kaveri?

[srai]

Is this real?


https://x.com/Rethik_D/status/1714526559305114009

First Tejas with Kaveri engine undergoing taxi Trial
-AIRFRAME:KH-2018:)
@ReviewVayu a shocker for you

[neerajb]

Looks photoshopped to me. No flaps/slats are down, not anchored so most likely taxiing. Why would you need reheat for taxiing?

[sanjayc]

^^ Read the Twitter thread. It is photoshopped.

The poster who posted this pix says this:

the pic on top is a edit,actual it's happening!

[williams]

The exhaust nozzle looks uncovered. Is that how they do taxi trails? It is also possible to take a picture from a lab test and Photoshop it. I think it it Photoshopped.

[Yogi_G]

Interesting. https://idrw.org/midhani-develops-high- ... lications/

[williams]

Interesting. https://idrw.org/midhani-develops-high- ... lications/

That is all good news, but we still need enough funding/investment to put together a Kaveri 2.0 and its variants in a reasonably short timeframe. We are starving all our fighter projects now and will become even more vulnerable when it is time to replace them. I am not sure Americans will be reliable suppliers once we have a direct conflict with their favorite Pakis or we become direct competitors to their lucrative export market.

[Nikhil_Naya]

Is this real?

https://x.com/Rethik_D/status/1714526559305114009

First Tejas with Kaveri engine undergoing taxi Trial
-AIRFRAME:KH-2018:)
@ReviewVayu a shocker for you

Photoshopped - but what is the buzz is that it is probably close to being mounted on a twin engine jet. RM visiting Russ...

[Rakesh]

Interesting. https://idrw.org/midhani-develops-high- ... lications/

Please do not post stuff from IDRW. The amount of yarns that dude spins out is astounding.

And if it is not a yarn, they he just shamelessly xerox copies from the internet and claims it as his own.

His all time best line ---> Sources close to IDRW stated, "....."

[Rakesh]

Photoshopped - but what is the buzz is that it is probably close to being mounted on a twin engine jet. RM visiting Russ...

https://x.com/SJha1618/status/1862877483504370160 ---> The Indian defence minister's forthcoming visit to Russia is probably going to be the most significant one in years.

[VishnuS]

Upping the thread, with a few tidbits on Kaveri program updates:

Recently there were a few reports that the Brahmos Aerospace has completed development of the AB for the Kaveri Dry engine, and that it's producing 29KN of "additional" (read Wet) thrust - the context of this "news" can be found in this old post.
However, this video report by Alpha Defense sort-of debunks it, by way of stating that, nothing of that kind of status-reporting by Brahmos Aerospace or by GTRE hasn't happened yet - and maybe during the AeroIndia 25, true status will emerge.

That said, this report does bring out a few more following points, in addition to those already reported earlier (refer to my post above):

1) In addition to developing the AB, Brahmos Aerospace is also entrusted with integrating the Kaveri Dry Engine with this new AB.
In this context, do note there were reports a few months back, that Godrej has already delivered a few Kaveri dry engines.

2) A new Fan was developed recently, and this new Fan when integrated with the already developed dry Kaveri, is producing 51KN dry thrust.
Again in this context, recall that the dry Kaveri version that was taken to Gromov Test Center, for high Altitude testing, had achieved 48.5KN dry thrust (expectation was 46KN).
Also remember, dev of this new Fan was reported, albeit completely disjointly, about an year or so back (will have to dig out that ref).

Bro... Any news about vibration during AB...

Vibration during AB was a primary concern and this is the reason we went for dry Kaveri...

Assuming Brahmos Aerospace fixes vibration during reheat and the there are no new issues with the fan... Can we start the twin engine aircraft testing!? Or Am I missing something other issues in Kaveri...

If the Kaveri and MiG 29 integration starts by Mid 2025, how long the testing process will be and will we Kaveri in MK1A? I understand that engine cowling and all that needs to be changed, but can we see it in at least in the last batch of MK1A delivery?? I just want some poetic ending to Tejas and Kaveri Saga.

[Yagnasri]

As far as I know, the vibrations and sound problems have already been addressed.

[SRajesh]

Photoshopped - but what is the buzz is that it is probably close to being mounted on a twin engine jet. RM visiting Russ...

https://x.com/SJha1618/status/1862877483504370160 ---> The Indian defence minister's forthcoming visit to Russia is probably going to be the most significant one in years.

Rakesh:
RM visiting Rus.
Putin coming to India
Trump starting Jan 20th
EAM saying trade will hit 100 billion with RUS
Something big is being cooked!
Or are we being too hasty in calculations!!

[Manish_P]

https://x.com/SJha1618/status/1862877483504370160 ---> The Indian defence minister's forthcoming visit to Russia is probably going to be the most significant one in years.

...
Something big is being cooked!
...

Or/and something stealthy

[drnayar]

...
Something big is being cooked!
...

Or/and something stealthy

Chakra 3

[maitya]

X-posting from Military Acquisitions thread ...

Russia, India and Jet Engine



- the usual preamble about how we don't yet have an engine for our Tejas jets
- some of our key existing jets depend on Russian engines
- seeking to manufacture improved versions of those engines
- Rajnath visiting Russia, may discuss those engines, nothing to do with Tejas

Precious little has been disclosed about the recently unveiled AL-31FN Series 5 engine - apart from wide-chord blade based Fan (no big deal wrt our current indigenous capability) and that 70% part commonality with AL-31FP (and other AL-31 legacy variants).

So, except for an enhanced thrust-level, not much to infer about anything i.e. this enhanced thrust must be from the bypass mass-flow (lighter Fan etc) component - which, for a relatively higher bypass design (~0.5 BPR), will not be a good news for hot-and-high situations here.
Instead, my hunch is, we are better served by allowing unrestricted "freedom" (wrt overall engine warranty applicability) to bring-in improved "indigenous parts" for the hot-section (and maybe for the cold sections as well).

But then again, I think the devil lies in the details - there's no guarantee that Russia would be agreeable to same-level-of-ToT for the AL-31FN series 5 mfg, as it did for AL-31FP.

Betw, we do Lic Mfg RD-33MK variant as well (in addition to RD-33 Series 3), so the Alpha defense report got that aspect slightly wrong.

[sanjayc]

Just wondering if GTRE creating a joint venture with ISRO to develop Kaveri would be a good idea

[pravula]

Just wondering if GTRE creating a joint venture with ISRO to develop Kaveri would be a good idea

No. It would be a good idea for GTRE to buy an old TU-22. We don't need Kaveri to go into space.

We need a test plane that can run supersonic, with redundant engines. With its huge bay, we can rig up a system to run the engine at speed, as long as it can be deployed and retracted.

[csaurabh]

I was watching one of the defence youtube channels where they said that Kaveri is now performing almost same as GE404 engine, it's just 150 kg heavier.

If this is true then we should straight up ditch F404 and use Kaveri. The Tejas has almost 10,000 kg of fuel+weapons carrying capacity. You can easily sacrifice a little bit of that and have the indigenous, albeit heavier engine. Does no one see the obvious solution ?

[williams]

I was watching one of the defence youtube channels where they said that Kaveri is now performing almost same as GE404 engine, it's just 150 kg heavier.

If this is true then we should straight up ditch F404 and use Kaveri. The Tejas has almost 10,000 kg of fuel+weapons carrying capacity. You can easily sacrifice a little bit of that and have the indigenous, albeit heavier engine. Does no one see the obvious solution ?

You are comparing an engine that is still under development to something that has been used by many fighters today. Also F-404 has been through incremental improvements from the 80s. IMO, there is no option right now other than running Tejas M !/1A with F-404s or an equivalent off the shelf engine. If we continue to develop Kaveri seriously and then figure out a way to mass manufacture them with reliability, perhaps we can think of them as a replacement engine later in the life cycle of these aircrafts. To start with, we need a reliable flying test bed to run these in real life conditions and make improvements as we observe its performance parameters. Also we need a thrust-to-weight ratio of at least > 1 to make it a viable engine. I would say we are still a decade away if we start with what we have today. It should be a national mission like IGMDP to develop various classes of supersonic turbofans. I hope somebody shows the leadership to start something like that.

[maitya]

I was watching one of the defence youtube channels where they said that Kaveri is now performing almost same as GE404 engine, it's just 150 kg heavier.

If this is true then we should straight up ditch F404 and use Kaveri. The Tejas has almost 10,000 kg of fuel+weapons carrying capacity. You can easily sacrifice a little bit of that and have the indigenous, albeit heavier engine. Does no one see the obvious solution ?

We can't ditch F404 in near foreseeable future - Kaveri (dry Kaveri from Godrej + AB from Brahmos Aerospace), even if it achieves 50KN/81KN** in its limited flight testing, near future (say in a year). As it will require an extensive testing and certification regime - minimum 5years, if not more.

So ditching F404-IN20, will put the entire Mk1A (83 + 97) program in jeopardy - as in next 5-6 years the first 83 Mk1A should have completed it's Mfg run and, maybe, the next mfg run of the next-97, would have got initiated.

So for us, the best approach is as follows:
1) Short-term (next 3 years):
a) Work with GE to ensure steady-flow of "fully imported" F404-IN20 version.
b) Ensure adequate funding is made available to the Kaveri program, so that test flight and full certification regime commences.
c) In parallel, after Kaveri has demonstrated the 50KN/80KN thrust levels (let's call this as baseline Kaveri, or maybe K9*), initiate the K10 program, with an aim to whittle down its weight to below 1T levels (say ~975Kg etc).
d) Start negotiating with GE, in parallel to the F414 Lic MFg deal, wrt sourcing F404 parts (especially the hot-section parts) from indigenous industries.
It can/should be staggered, starting from cold section parts (Fan and Compressor stages, casings, Acc Gear Box etc), then on to static Hot section (Combustor, seals, A/B parts etc), finally onto the remaining Hot Section parts (Turbine blades/discs, Vanes, Shafts etc).

2) Medium Term (3 - 5 years):
a) Complete certification of the baseline Kaveri (K9*) - initiate flight testing/certification of the K10 version (this should take ~2 years or so, as the K9* is already certified).
b) Negotiate with GE, alongwith the implementation of F414-INS6 Lic-Mfg agreement, so that:
i) all parts of the last 50% (so ~45) of the 99 F404-IN20, is sourced from indigenous industry sources - however final assembly, integration and testing remains with GE.
ii) so that a token number, say last 20% (so ~19-20), is Lic-Mfg/assembled (and tested) by an Indian entity - either by HAL or via a Lic Mfg JV (GE + Private Entity) - but under GE warranty.
iii) an indigenous part-replacement-for-perf-improvement program (let's call it F404-IN20-MKI), without voiding the whole-product-level guarantee/warranty from OEM(GE), is put in place.
c) Initiate the follow-on Kaveri+ program (refer to various news items in this thread), towards 62KN/98KN class TF dev work

3) Long Term (5-7 years):
a) Complete K10 certification and move to serial mfg of the K10 turbofans, for the next 97 Mk1A.
The entire TF requirement for this batch (of 97Mk1As) can be split between K10 and the "improved"-and-fully-indigenously-mfg F404-IN20-MKI version.
b) Start negotiating with GE wrt the F414-INS6, similar to point 2b above - for the ongoing MK2/TEDBF programs.

4) Ultra Long Term (7+ years):
a) Complete the Kaveri+ program (including flight testing and certification).
b) For all 2nd and 3rd TF replacements for the MK1As, move to sourcing exclusively from the K10 stable.
c) Repeat 3a wrt Kaveri+, for residual MK2/TEDBF etc programs

Lastly, let me assuage the import-pasand-shills here who have already-started shivering-in-their-collective-dhotis - tck! tck!!
Do not fear, your imported-TF-gravy-train will continue unabated, as nothing of the sort outlined above, is ever going to happen here.
It's already too much to comprehend for the medieval-history-degree-dhari Baboons, let alone securing funding and designing (and implementing) such a strategic program etc.

Oh Well ...
==========================t======================================================================
** Note a flat-rated 50KN/81KN TF is way better wrt real-world thrust performance (in our operating env context), than some 54KN/86KN non-flat-rated TF like F404-IN20.
Also do note this flat-rating, doesn't mean same thrust is maintained at all operating ambient temp levels and altitudes - normally, in our context, flat-rating is limited to ISA SLS + 30deg C levels.

ISA - International Standard Atmosphere
SLS - Sea Level Static (SLS)

[williams]

I was watching one of the defence youtube channels where they said that Kaveri is now performing almost same as GE404 engine, it's just 150 kg heavier.

If this is true then we should straight up ditch F404 and use Kaveri. The Tejas has almost 10,000 kg of fuel+weapons carrying capacity. You can easily sacrifice a little bit of that and have the indigenous, albeit heavier engine. Does no one see the obvious solution ?

We can't ditch F404 in near foreseeable future - Kaveri (dry Kaveri from Godrej + AB from Brahmos Aerospace), even if it achieves 50KN/81KN** in its limited flight testing, near future (say in a year). As it will require an extensive testing and certification regime - minimum 5years, if not more.

So ditching F404-IN20, will put the entire Mk1A (83 + 97) program in jeopardy - as in next 5-6 years the first 83 Mk1A should have completed it's Mfg run and, maybe, the next mfg run of the next-97, would have got initiated.

So for us, the best approach is as follows:
1) Short-term (next 3 years):
a) Work with GE to ensure steady-flow of "fully imported" F404-IN20 version.
b) Ensure adequate funding is made available to the Kaveri program, so that test flight and full certification regime commences.
c) In parallel, after Kaveri has demonstrated the 50KN/80KN thrust levels (let's call this as baseline Kaveri, or maybe K9*), initiate the K10 program, with an aim to whittle down its weight to below 1T levels (say ~975Kg etc).
d) Start negotiating with GE, in parallel to the F414 Lic MFg deal, wrt sourcing F404 parts (especially the hot-section parts) from indigenous industries.
It can/should be staggered, starting from cold section parts (Fan and Compressor stages, casings, Acc Gear Box etc), then on to static Hot section (Combustor, seals, A/B parts etc), finally onto the remaining Hot Section parts (Turbine blades/discs, Vanes, Shafts etc).

2) Medium Term (3 - 5 years):
a) Complete certification of the baseline Kaveri (K9*) - initiate flight testing/certification of the K10 version (this should take ~2 years or so, as the K9* is already certified).
b) Negotiate with GE, alongwith the implementation of F414-INS6 Lic-Mfg agreement, so that:
i) all parts of the last 50% (so ~45) of the 99 F404-IN20, is sourced from indigenous industry sources - however final assembly, integration and testing remains with GE.
ii) so that a token number, say last 20% (so ~19-20), is Lic-Mfg/assembled (and tested) by an Indian entity - either by HAL or via a Lic Mfg JV (GE + Private Entity) - but under GE warranty.
iii) an indigenous part-replacement-for-perf-improvement program (let's call it F404-IN20-MKI), without voiding the whole-product-level guarantee/warranty from OEM(GE), is put in place.
c) Initiate the follow-on Kaveri+ program (refer to various news items in this thread), towards 62KN/98KN class TF dev work

3) Long Term (5-7 years):
a) Complete K10 certification and move to serial mfg of the K10 turbofans, for the next 97 Mk1A.
The entire TF requirement for this batch (of 97Mk1As) can be split between K10 and the "improved"-and-fully-indigenously-mfg F404-IN20-MKI version.
b) Start negotiating with GE wrt the F414-INS6, similar to point 2b above - for the ongoing MK2/TEDBF programs.

4) Ultra Long Term (7+ years):
a) Complete the Kaveri+ program (including flight testing and certification).
b) For all 2nd and 3rd TF replacements for the MK1As, move to sourcing exclusively from the K10 stable.
c) Repeat 3a wrt Kaveri+, for residual MK2/TEDBF etc programs

Lastly, let me assuage the import-pasand-shills here who have already-started shivering-in-their-collective-dhotis - tck! tck!!
Do not fear, your imported-TF-gravy-train will continue unabated, as nothing of the sort outlined above, is ever going to happen here.
It's already too much to comprehend for the medieval-history-degree-dhari Baboons, let alone securing funding and designing (and implementing) such a strategic program etc.

Oh Well ...
==========================t======================================================================
** Note a flat-rated 50KN/81KN TF is way better wrt real-world thrust performance (in our operating env context), than some 54KN/86KN non-flat-rated TF like F404-IN20.
Also do note this flat-rating, doesn't mean same thrust is maintained at all operating ambient temp levels and altitudes - normally, in our context, flat-rating is limited to ISA SLS + 30deg C levels.

ISA - International Standard Atmosphere
SLS - Sea Level Static (SLS)

Very solid plan. I wonder if we can let a private sector company (or consortium of companies) manage the program and let them work out the deals with GE. They make the money selling the engines to Indian and export market. Govt/DRDO/GTRE can help with handholding and provide IP rights for things that is already in the know.

[Kailash]

Maitya ji, I don't see the French in your long post defining the short medium long and ultra long term plans. Was this deliberate? Do we not need them in the mix?

[maitya]

Maitya ji, I don't see the French in your long post defining the short medium long and ultra long term plans. Was this deliberate? Do we not need them in the mix?

Well, the context of that post was wrt F404/F414-class 4.0-4.5Gen TF options i.e. 80-100KN class ... but if you are alluding to 5th Gen TF for AMCA (in 120-130KN class), then it's a different story all-together.
Actually, the AMCA TF imbroglio has become so convoluted nowadays, it's difficult to think this one thru.

My personal view is, since both of the two OEMs (Rolls Royce and Safran) vying for this now, don't have an operational 5th Gen TF product, it'd be too risky for us to have a single track D&D path for this. There are innumerable technological hurdles/risks, plus it doesn't take a lot for the OEM to simply refuse to part with (as part of ToT) key technological D&D aspects - instead some Lic Mfg tech lollypop (e.g. "mfg from raw material" ala AL-31FP Lic Mfg program) will get handed down.
Most of these contracts are anyway not worth the paper on which they are written.

The remedy ofcourse is, to have 2 parallel programs with these 2 OEMs, but then again we are not a country of unlimited resources, to be able to fund such an endeavor. For example, Safran had been reported to quote upwards of $6B, for this D&D program, and looks like they have refused to "accommodate" anything, from their overdue offset obligations (from Rafale procurements) against this program. I'd presume, the RR "offers" would be of the same ballpark range, maybe slightly lesser.

So the only other option is to have a parallel indigenous 5th Gen TF D&D program.
Always remember, we have sufficient technological base to graduate to 130KN-class TF, which even if not a true-blue 5th GEn TF, will be quite close to it wrt multiple 5th Gen TF technologies*.
(You may have to refer to my previous posts on this thread to appreciate this fact)
However, trouble is, without any fully-developed TF operational experience (and also a proven mass-manufacturing base for ALL components of a 4/4.5Gen TF), the confidence wrt embarking on such an endeavor is simply not there.

Also do note, that the only countries today who have any operational 5th Gen TFs, are basically US (GE and P&W) and Russia (Saturn via Izdeliya-30) - and all the relevant 5th Gen TF Tech that we are looking at mastering via this program, all are available with these two OEMs. However, as expected, they are very cagey about sharing any of it (and rightly so).

So IMVHO we need to have a parallel indigenous 5th Gen D&D program, in a co-development mode, ideally with US (read GE, via a follow-on to their F414-EPE program), but if that is not going to work out, then with Russia (read Saturn, again via a follow-on to their Izdeliya-30 program). This co-dev mode would entail more of consultancy and hand-holding to GTRE (and other agencies) and also some amount of Tech sharing.

This will be a nice hedge against any shenanigans by RR/Safran in our AMCA TF joint-D&D initiative, as and when it happens.

And this program, if pursued, needs to happen in parallel to the K10 program (so in next 2 years with a 5-7 year horizon), as some of the technologies involved are common wrt trying to reduce the engine weight.
None of these, of course, would be cheap ...

==================================================================================================================
*Some of the 5th Gen TF tech are:
1) Adaptive Cycle design
2) CMC based LPT blades and disks (Bling Architecture), also for HPC last stage(s)
3) Secondary loss management in the HPC stages (incl compressor blade surface mgmt tech)
4) Transpiration cooling tech for NGV
5) Rub-tolerant coatings
6) Bi-layer TBC
7) Fluidic TV
etc etc

[basant]

Wouldn't it be better to go for higher thrust even if it means higher weight with available tech? It is prudent to design an aircraft around an engine rather than design an engine for an a/c that requires next-gen technologies given our immediate requirements. In such a case, a redesign of TEDBF with plausible desi engine, compatible with an interim available engine, would be both desirable and sensible. No one says Rafale is worse vis-a-vis F-18 because it has lower thrust engine! The entire saga reminds me of lifts on Vikramaditya.