Kaveri & Aero-Engine: News & Discussion

[fanne]

I have a simple question - If Kaveri non after burner has been successful, and it is good to go in Ghatak (the tender is out to procure 75 of them, must be reliable enough to go in a unmanned plane), why we keep on saying that core has failed and we need M-88 core. It looks like, non afterburner is working fine and the afterburner is where we have to focus (maybe more bypass?).
OR
Is that the screeching, oscillation problem etc was during the non afterburner part and that is not stable?

[Indranil]

Agupta sahab. You still think Kaveri engine is not up to flight testing stage yet?

[LakshmanPST]

Taepodong
@stoa1984
·
Jan 20
Finally, WS10 and J-10 survived thanks to Su-27 project. China used an entire heavy double engine fighter fleet to build-up WS10 reliability and progress. Would result in so many crashes if J10 is fitted with early batch WS10.

...

I think we can try something similar with TEDBF/ORCA to test Kaveri in future once the jets are ready...

[Indranil]

Breaking : HTFE-25 Core Engine Sea Level Trials Successful: The team of AERDC achieved a milestone with successful competition of Hindustan Turbo Fan Engine (HTFE)- 25 sea level trials at Tambaram Air Force Station, Chennai.....1/2

https://twitter.com/ReviewVayu/status/1 ... 11137?s=19

....2'2 Core engine of HTFE-25 was tested for various phases including starting trials with indigenously designed and developed Air Producer (AP) and Air Turbine Starter (ATS). Light-up trials with different fuel flow settings/air inlet temperature condition were carried out.

https://twitter.com/ReviewVayu/status/1 ... 92896?s=19

Excellent news. Another engine that needs to go into flight testing. I wonder what they would do. May be power a Hawk with this engine?

This engine has so much potential. It can be the engine for all our IJTs and AJTs. I really hope they fully develop it to its full potential of 35 kN dry thrust. My wet dream is an afterburning version with 50-55 kN of wet thrust. I believe we can design a great light fighter for airforces with lesser means. A modern day Mig-21 and F-5. The type trianer would be India's next generation AJT.

The high bypass version can be used for a 60-70 seater.

[srin]

^^^
They could try it on the Jaguar first. Would be a good test-bed, because it is twin engine and similar class.

[chetak]

Agupta sahab. You still think Kaveri engine is not up to flight testing stage yet?

Indranil: Are you asking w.r.t the item re. HTFE-25 ?

Its hard to link the two that way (for me). A more plausible (hopefull?) tack might be that the team learnt from the Kaveri experience and chose to avoid the problem areas (design envelopes, component design points) in their conceptual/preliminary design that came up... perhaps aeromechanical instabilities, HPT conditions that stressed thermal life etc - so HTFE 25 may be somewhat conservative (or) smarter and therefore has a better chance of success. And/or the development process will be better because we've learnt to test/re-design for phenomena we didn't know when we did Kaveri.

Its frustrating to be so in the dark about Kaveri. The only definitive thing we seem to have to go on is the DRDO chief explicitly shutting it down, saying we've learnt a lot, and have to work on some technologies. Thats pretty straight (after 2 decades of obfuscating) and blows away all this dry thrust/wet thrust khayali-biryani-making on BRF.

In some sense, its great that the teams have dual tracks --> (a) make HTFE-25 a success and (b) master the technologies that we can come back to Kaveri or Kaveri++ (for AMCA) with more confidence

and the unsaid moral of the story is: there are other teams out there as well that can make jet engines.

another myth carefully nurtured over the decades now busted

[Indranil]

No. No. I am not conflating HTFE25. I was very happy when HAL took up the HTFE. I don't know if they have met design targets. But if they have then it is better the F124! And they have come up to speed in good time. I don't know how they would flight test it, but let's keep our fingers crossed.

The truth about Kaveri is somewhere in between the uninformed bashing that it receives and the adulation in this forum. The truth is that Kaveri non-afterburning engine is entering production. EOI is out for a potential 80 engine production run. It cannot be without a modicum of success. On other hand Kaveri for LCA variants won't happen.

I think India should join hands with Japan for a common engine development for their next generation fighters.

[chetak]

No. No. I am not conflating HTFE25. I was very happy when HAL took up the HTFE. I don't know if they have met design targets. But if they have then it is better the F124! And they have come up to speed in good time. I don't know how they would flight test it, but let's keep our fingers crossed.

The truth about Kaveri is somewhere in between the uninformed bashing that it receives and the adulation in this forum. The truth is that Kaveri non-afterburning engine is entering production. EOI is out for a potential 80 engine production run. It cannot be without a modicum of success. On other hand Kaveri for LCA variants won't happen.

I think India should join hands with Japan for a common engine development for their next generation fighters.

HAL has begun some work on the HTFE afterburner too and they seem to have started testing a preliminary version of the afterburner already.

[maitya]

<snip>
The truth about Kaveri is somewhere in between the uninformed bashing that it receives and the adulation in this forum. The truth is that Kaveri non-afterburning engine is entering production. EOI is out for a potential 80 engine production run. It cannot be without a modicum of success.
<snip>
On other hand Kaveri for LCA variants won't happen.
<snip>
I think India should join hands with Japan for a common engine development for their next generation fighters.
<snip>

A couple of points wrt the above:

1) Kaveri Core is a unqualified/unbashed success
In fact would have been ahead of its time, if it had got flight qualified around 2010-2012 etc, but since it didn't no point in taking about it's "greatness" etc.
The "popular issues" that are normally pointed out everywhere (e.g. overweight, Wet Thrust shortfall etc) doesn't have anything to do with the Core - but then again basic understanding of the Core vs rest-of-the-system in a modern turbofan is required - that's been the endeavor for some of us in this forum (albeit with very limited success, so far ).


2) Kaveri, as a turbofan engine for Indian conditions, is better than F404
But, at the same time, it needed to somehow morph to a F414 level overnight, to get into a LCA (so not an Kaveri issue as such) - that's Djinn magic etc territory used extensively in our western neighborhood.
Not possible to go to 414 level without major rework on the Core itself - but nobody would want to go that route without certifying the current engine as a whole.
Hence is our clamor to spend a little more and get it certified on as-is state - benefits are huge!!!

More on this point, some other day - but just as a teaser, will delve into,
a) why certain (very very few) Kaveri perf/design parameters look inferior to that of F404
b) how even those can be changed to beat F404 and maybe declare a pyrrhic victory - but since those will still not take it F414 level, will be of no use


3) Turbofan development is not Turbofan-Core development only
GTRE/DRDO faltered with this mindset and, from what I'm seeing from whatever little has come from various interviews from the HTFE team, they have the exact same mindset.
i.e. Core is the by-all-and-end-all aspect, put 100% focus on it
So, most probably, they will also fail, exactly where Kaveri team failed.
Not very surprising there, as majority of the then GTRE team was basically the HAL's engine division folks, artificially carved out and renamed in 80s.


4) HTFE etc, though a very very good start, is nowhere near what Kaveri is, at a technological level.
Getting to those levels will be ultra steep and time (and budget) consuming - also it's current design philosophy is such that it can't be ported to F414 level turbofan dev.

So combining 2 and 4 above, it's almost a non-brainer:
If a F414 level turbofan had to be developed indigenously, which Turbofan-Core should be the starting point.
But I have 0-hope that such common sense logic will even reach funding-class (i.e. MoD Baboons and what ever chai-biskoot committees that will get setup for countless recommendations (which normally are not going to be heeded to, anyway - so except for wasting time, no harm done).


5) Decouple indigenous Turbofan development with Platform (e.g. AMCA) dev programmes
Instead go for Lic-Mfg of a wholly imported turbofan engine for that platform programmes.
"Joint dev" for a national-level-and-strategic-cutting-edge-technological-capability platforms like Turbofans, are a eye-wash, so not sure whom do we try to fool (except for ourselves).
Run indigenous parallel programmes with the platform usage in mind - with IAF onboard wrt allowing limited/partial sqn service of platforms with indigenous engines (aka let 22-platform LCA sqns have 3-Kaveri-equipped-LCAs, so that IAF's operational capability is not degraded at the sqn level).

[arvin]

I think India should join hands with Japan for a common engine development for their next generation fighters.

Japan had to tap GE expertise for the core of its Hondajet which had a modest thrust of 9.2kn.
Jet engine design wise both us and them looks like are at same level. Best to develop IP based on own money and effort and then enter partnership like CFM or Eurojet consortium.

[Indranil]

HAL has begun some work on the HTFE afterburner too and they seem to have started testing a preliminary version of the afterburner already.

This is just music to my ears. I had no clue. Dil khush kar diya aapne!

[Indranil]

I think India should join hands with Japan for a common engine development for their next generation fighters.

Japan had to tap GE expertise for the core of its Hondajet which had a modest thrust of 9.2kn.
Jet engine design wise both us and them looks like are at same level. Best to develop IP based on own money and effort and then enter partnership like CFM or Eurojet consortium.

I would not enter a consortium with anybody who could get there just by virtue of funding. We might get a engine out of it, but we would not learn how to design our one.

I like Japan's development of the F-3, XF5, F-7 and XF 9 series of engines. They produce a little more than 9.2 kNs

[nam]

Do we know, why Kaveri is having thrust shortage in afterburner? Is it a case material or design fault?

Would further testing help us find out the issue? Or we already know the reason and it is material?

The weight is not a major concern, as the resultant platform can be designed to manage the extra weight & CoG.

[hgupta]

Most likely it has to do with withstanding and sustaining higher temperatures that comes with AB or sufficient fuel flow to sustain AB thrust.

[chetak]

HAL has begun some work on the HTFE afterburner too and they seem to have started testing a preliminary version of the afterburner already.

This is just music to my ears. I had no clue. Dil khush kar diya aapne!

Core-1 and Core-2, two engines have been produced and completed 339 runs as of 2019 out of which 96 runs were conducted in 2018-19.

Engine has successfully completed cold starting test at 14 °C with spark igniters and has also achieved 100 per cent max speed with and without IGV modulation.

The company has also initiated the development for integrating afterburner technology on engine.

In March 2019, first test with "basic afterburner" configuration was conducted on the engine

[chola]

Taepodong
@stoa1984
·
Jan 20
Finally, WS10 and J-10 survived thanks to Su-27 project. China used an entire heavy double engine fighter fleet to build-up WS10 reliability and progress. Would result in so many crashes if J10 is fitted with early batch WS10.

...

I think we can try something similar with TEDBF/ORCA to test Kaveri in future once the jets are ready...

Yes, and in fact we can even induct with an uprated Kaveri for those if we are willing to accept specs lesser than the F414 for the sake of our industry. The chinis did that by accepting the early production models of the WS-10 for the J-11B.

Just like Cheen, we won't be able to beat the established players in our first try. But we need to accept that first try so the subsequent attempts can happen. Every new mark will advance the industry. If you won't accept that first one then things will never get off the ground.

[chola]

Japan had to tap GE expertise for the core of its Hondajet which had a modest thrust of 9.2kn.
Jet engine design wise both us and them looks like are at same level. Best to develop IP based on own money and effort and then enter partnership like CFM or Eurojet consortium.

I would not enter a consortium with anybody who could get there just by virtue of funding. We might get a engine out of it, but we would not learn how to design our one.

I like Japan's development of the F-3, XF5, F-7 and XF 9 series of engines. They produce a little more than 9.2 kNs

Indranil, the F-7 high-bypass for their P-1 MPA is 60kN. High-bypass means no AB but they already have a core that is equivalent of a medium fighter engine.

@arvin, no we are not at the same level yet. The Japanese turbofans are powering both test and production aircraft. Ours have not. They have reams of flight data that we do not.

I think a partnership with them is worth the effort. Unlike the big four (US/UK/France/Russia) we might be on more of a equal footing with them on the sharing of IP. Unlike the AL-31 we are making for the MKI and MKI onlee, we need to be building engines that we control.

[Indranil]

I would not enter a consortium with anybody who could get there just by virtue of funding. We might get a engine out of it, but we would not learn how to design our one.

I like Japan's development of the F-3, XF5, F-7 and XF 9 series of engines. They produce a little more than 9.2 kNs

Indranil, the F-7 high-bypass for their P-1 MPA is 60kN. High-bypass means no AB but they already have a core that is equivalent of a medium fighter engine.

@arvin, no we are not at the same level yet. The Japanese turbofans are powering both test and production aircraft. Ours have not. They have reams of flight data that we do not.

I think a partnership with them is worth the effort. Unlike the big four (US/UK/France/Russia) we might be on more of a equal footing with them on the sharing of IP. Unlike the AL-31 we are making for the MKI and MKI onlee, we need to be building engines that we control.

F-7 is high bypass variant of XF-5, which is the next generation development from the F3-400 which never went into production. The F3 which is the non afterburning variant however powers the T-4 trainers.

[Raman]

Apologies if this was posted earlier. On RSTV 23rd Jan 2020.

[chetak]

This is just music to my ears. I had no clue. Dil khush kar diya aapne!

Core-1 and Core-2, two engines have been produced and completed 339 runs as of 2019 out of which 96 runs were conducted in 2018-19.

Engine has successfully completed cold starting test at 14 °C with spark igniters and has also achieved 100 per cent max speed with and without IGV modulation.

The company has also initiated the development for integrating afterburner technology on engine.

In March 2019, first test with "basic afterburner" configuration was conducted on the engine

Boost for 'Make in India': HAL's 25 kN aero engine completes inaugural run; can be used for trainer aircraft





Also known as the Hindustan Turbo Fan Engine (HTFE-25), it can be used for basic, intermediate and advanced trainer aircraft. The engine can also be used on business jets and five ton weight class aircraft in single engine configuration and on aircraft of up to nine ton weight class with twin engine configuration.

Parrikar also launched the design and development project of Hindustan Turbo Shaft Engine (HTSE-1200) which can be used for helicopters

The HTSE-1200 can be used for helicopters of 3.5 ton class in the single engine configuration (e.g. LUH) and for 5 to 8 ton class in twin engine configuration (e.g. ALH, LCH). The engine develops a power of 1200 kW at sea level and can operate up to an altitude of 7 km. This project too is undertaken by HAL with its internal resources with an aim of developing the capability of indigenous design and development of turboshaft engines.

Complimenting HAL for undertaking these projects, Parrikar said all out efforts should be made to achieve maximum in the aeronautical engineering with active participation of HAL and the private sector together. "The recent expansion of activities in the aerospace sector as seen in HAL and has potential to turn India into aerospace manufacturing hub. The country would need 4000 to 6000 helicopter engines in the coming years and efforts of HAL to in this direction needs to be appreciated," Parrikar said.

T Suvarna Raju, CMD of HAL said successful running of the 25 kN engine is one of the major mile-stones achieved by the company in its platinum jubilee year contributing to Make-in-India efforts of the government.

"Aero Engine Research & Design Centre (AERDC), HAL, Bengaluru had taken up the Design and Development of a 25 kN thrust class turbofan engine for basic military trainer aircraft. HAL used its internal resources with an aim of producing indigenously designed and developed aero engines in a time frame of six years beginning from 2013. In the first phase of the programme, the design of the full engine and manufacture and testing of the technology demonstrator of the core engine are covered. In the subsequent phases the manufacture and testing of the full engine will follow," the press release said.

Specifications
Data accumulated from various sources (please correct wherever you find)

General characteristics
Type: Turbofan
Length: 1730mm
Diameter: 590mm
Dry weight: 350kg
Components
Compressor: not known
Turbine: not known
Performance
Maximum thrust: 25kN(Dry)/ 35-40kN (Wet thrust expected)
Overall pressure ratio: 20.43
Bypass ratio: 0.50
Fuel consumption: 0.71kg/kgf-hr
Thrust-to-weight ratio: 5.66
Air Mass Flow: 43 kg/s
Max Flight Altitude: 11km
Turbine Entry Temperature: 1450 K

[csaurabh]

Composite fan blade manufacture., note the amount of manual work needed

Here is what I noted in that video:

Carbon fibre laminate roll being mounted
Laser cutting ( or perhaps milling ) to cut the laminate into desired shapes
Placement of the laminate parts into the mould ( manual layup, long time )
Adding vacuum bag, put into autoclave for resin injection ( curing time not shown )
Putting some type of tape on the outside surface, not sure why
CNC milling operation ( for getting dimensional tolerances )
CMM for measuring the dimensions
A lot of robotic handling operations using cables and fixtures
Robotic spray painting ( to get an even paint thickness )
CNC milling again
CMM again
Moment of inertia testing? Not sure
Blades being put away in a chamber

All of the above facilities we are having, more or less. At ISRO I have seen, and probably at NAL. So we can probably make the composite fan blades.

But the fan blades are not the problem with the jet engine. It is the hot section and turbine blades, for which the normal composites cannot withstand the temperatures. You need CMC composites for that, and CMC technology is barely there in India at all to my knowledge.

[arvin]

I like Japan's development of the F-3, XF5, F-7 and XF 9 series of engines. They produce a little more than 9.2 kNs

they have 16kN, 49kN, 60kN and 107kN thrust.

[fanne]

What is cmc composites?

[NRao]

What is cmc composites?

2015 vid.



2018 vid.

[fanne]

Something we should have also started few years ago @ NAL? Still not too late for one of the lab to start this - perhaps a directive from PMO with budget

[Rakesh]

https://twitter.com/SJha1618/status/122 ... 48835?s=20 ---> The effort to build a fighter class 110 KN wet-thrust low-bypass turbofan (jet engine) has to be done under the aegis of a special purpose vehicle which will have both public and private stakeholders. I don't see a way around this.

https://twitter.com/SJha1618/status/122 ... 63040?s=20 ---> For India these have to get off the ground in the next 2 years.

1. 22-28 nm node semifab, with Gallium Nitride (GaN) based fabrication capability as well.

2. A special purpose vehicle to develop & then build a 110 KN low-bypass turbofan (jet engine) successor to the Kaveri.

[chola]

Something we should have also started few years ago @ NAL? Still not too late for one of the lab to start this - perhaps a directive from PMO with budget

It is never too late for lab to develop anything but can what they develop be manufactured locally?

https://twitter.com/SJha1618/status/122 ... 48835?s=20 ---> The effort to build a fighter class 110 KN wet-thrust low-bypass turbofan (jet engine) has to be done under the aegis of a special purpose vehicle which will have both public and private stakeholders. I don't see a way around this.

https://twitter.com/SJha1618/status/122 ... 63040?s=20 ---> For India these have to get off the ground in the next 2 years.

1. 22-28 nm node semifab, with Gallium Nitride (GaN) based fabrication capability as well.

2. A special purpose vehicle to develop & then build a 110 KN low-bypass turbofan (jet engine) successor to the Kaveri.

The 110kN will be a cutting edge project like the Kaveri was in the 1980s. We never got the Kaveri into production so we still have no experience there.

GTRE's experience in designing, building and testing the prototypes will help but unless we make some attempt to mass produce the Kaveri (with AB) then we are still in square one. Maybe the non-AB version for Ghatak will help out in the experience front.

But I like to see us use and produce the Kaveri in a jet while we develop the 110kN engine so that when it is ready we would have had production experience with the Kaveri.

[arvin]

Sjha is spot on wrt to SPV. Something like Antrix Ltd equivalent for DRDO will have to created. Or take GTRE out of DRDO and make it GTRE Ltd.

[fanne]

Can we develop a swept wing, dual engine UAV (swept wing for higher Mach, like say .7 Mach), a very stable plane, with guaranteed auto landing and take off, and not much other sub systems. One engine fitted with any proven engine - Adour, RD-33, f404, al31f and other for Air testing of any engine under development.

[maitya]

Boost for 'Make in India': HAL's 25 kN aero engine completes inaugural run; can be used for trainer aircraft


<snip>

Specifications
Data accumulated from various sources (please correct wherever you find)

General characteristics
Type: Turbofan
Length: 1730mm
Diameter: 590mm
Dry weight: 350kg
Components
Compressor: not known
Turbine: not known
Performance
Maximum thrust: 25kN(Dry)/ 35-40kN (Wet thrust expected)
Overall pressure ratio: 20.43
Bypass ratio: 0.50
Fuel consumption: 0.71kg/kgf-hr
Thrust-to-weight ratio: 5.66
Air Mass Flow: 43 kg/s
Max Flight Altitude: 11km
Turbine Entry Temperature: 1450 K

Here's the comparo between Kaveri and HTFE - something that Indranil had asked for many months back, but never got the b/w to get to it.
Anyway here it is ... will analyse etc later!!!

[Indranil]

You are very close with those first order calculations. At AI'19, the gent presenting HTFE said that the engine can easily go up to 35 kN of thrust. I am assuming he meant dry thrust.

Above post belongs to gyan-only I made for you. Let me know if you are having a problem posting there.

[Rakesh]

Ready to partner India, transfer technology of jet engine: Safran
https://m.economictimes.com/news/defenc ... 950370.cms
By Manu Pubby, 05 Feb 2020

[Indranil]

Ready to partner India, transfer technology of jet engine: Safran
https://m.economictimes.com/news/defenc ... 950370.cms
By Manu Pubby, 05 Feb 2020

Ghanta. Jab sahi mein paisa deke collaboration maanga, tab nahi diya! Rafale ke saath maanga, tab nahi diya. Ab muft mein doge. Ghanta!!!

BS. Wein we entered a legal and binding collaboration, nothing was given. When we asked for it as part of the Rafale deal, it was not given. Are we supposed to trust empty words now. I cry "wolf!"

[nachiket]

Whenever anyone says the words "We will transfer Jet Engine technology" you can safely point a finger at them and call them a liar because that will always be the case.

[V_Raman]

I dont fully understand why Kaveri as it exists cannot be mated to a LCA and at least ground tested.

[Rakesh]

https://twitter.com/sjha1618/status/122 ... 39490?s=21 —> I think Safran and Rolls Royce are front-runners in the race to emerge as a foreign collaborator for India's effort to develop a build a 110 KN low-bypass turbofan (jet engine) for powering the Advanced Medium Combat Aircraft.

[ks_sachin]

I dont fully understand why Kaveri as it exists cannot be mated to a LCA and at least ground tested.

Ground testing is not the gap....

[kit]

Ready to partner India, transfer technology of jet engine: Safran
https://m.economictimes.com/news/defenc ... 950370.cms
By Manu Pubby, 05 Feb 2020

Ghanta. Jab sahi mein paisa deke collaboration maanga, tab nahi diya! Rafale ke saath maanga, tab nahi diya. Ab muft mein doge. Ghanta!!!

BS. Wein we entered a legal and binding collaboration, nothing was given. When we asked for it as part of the Rafale deal, it was not given. Are we supposed to trust empty words now. I cry "wolf!"

What better proof that India is within its goal of self reliance in Jet engine tech ? ., it may not be the state of the art now, but it will get there ..

[maitya]

I dont fully understand why Kaveri as it exists cannot be mated to a LCA and at least ground testedflown in regular squadrons as squadron reserve platforms.

There, corrected it for you ...

[JayS]

You are very close with those first order calculations. At AI'19, the gent presenting HTFE said that the engine can easily go up to 35 kN of thrust. I am assuming he meant dry thrust.

Above post belongs to gyan-only I made for you. Let me know if you are having a problem posting there.

Not dry but wet, in this context ie the intended Mil application. But in other context, as a high BPR civil jet engine for Business jet class like the Falcon series, it could.I think.